0001104659-13-070740.txt : 20130918 0001104659-13-070740.hdr.sgml : 20130918 20130918145940 ACCESSION NUMBER: 0001104659-13-070740 CONFORMED SUBMISSION TYPE: 485BPOS PUBLIC DOCUMENT COUNT: 8 FILED AS OF DATE: 20130918 DATE AS OF CHANGE: 20130918 EFFECTIVENESS DATE: 20130918 FILER: COMPANY DATA: COMPANY CONFORMED NAME: UBS MONEY SERIES CENTRAL INDEX KEY: 0001060517 IRS NUMBER: 134010447 STATE OF INCORPORATION: DE FISCAL YEAR END: 0430 FILING VALUES: FORM TYPE: 485BPOS SEC ACT: 1933 Act SEC FILE NUMBER: 333-52965 FILM NUMBER: 131103455 BUSINESS ADDRESS: STREET 1: C/O UBS GLOBAL ASSET MANAGEMENT (AMERICA STREET 2: 12TH FLOOR 1285 AVENUE OF THE AMERICAS CITY: NEW YORK STATE: NY ZIP: 10019 BUSINESS PHONE: 212-821-3000 MAIL ADDRESS: STREET 1: C/O UBS GLOBAL ASSET MANAGEMENT (AMERICA STREET 2: 12TH FLOOR 1285 AVENUE OF THE AMERICAS CITY: NEW YORK STATE: NY ZIP: 10019 FORMER COMPANY: FORMER CONFORMED NAME: BRINSON MONEY SERIES DATE OF NAME CHANGE: 20010625 FORMER COMPANY: FORMER CONFORMED NAME: MITCHELL HUTCHINS LIR MONEY SERIES DATE OF NAME CHANGE: 19990730 FORMER COMPANY: FORMER CONFORMED NAME: MITCHELL HUTCHINS INSTITUTIONAL SERIES DATE OF NAME CHANGE: 19980427 FILER: COMPANY DATA: COMPANY CONFORMED NAME: UBS MONEY SERIES CENTRAL INDEX KEY: 0001060517 IRS NUMBER: 134010447 STATE OF INCORPORATION: DE FISCAL YEAR END: 0430 FILING VALUES: FORM TYPE: 485BPOS SEC ACT: 1940 Act SEC FILE NUMBER: 811-08767 FILM NUMBER: 131103456 BUSINESS ADDRESS: STREET 1: C/O UBS GLOBAL ASSET MANAGEMENT (AMERICA STREET 2: 12TH FLOOR 1285 AVENUE OF THE AMERICAS CITY: NEW YORK STATE: NY ZIP: 10019 BUSINESS PHONE: 212-821-3000 MAIL ADDRESS: STREET 1: C/O UBS GLOBAL ASSET MANAGEMENT (AMERICA STREET 2: 12TH FLOOR 1285 AVENUE OF THE AMERICAS CITY: NEW YORK STATE: NY ZIP: 10019 FORMER COMPANY: FORMER CONFORMED NAME: BRINSON MONEY SERIES DATE OF NAME CHANGE: 20010625 FORMER COMPANY: FORMER CONFORMED NAME: MITCHELL HUTCHINS LIR MONEY SERIES DATE OF NAME CHANGE: 19990730 FORMER COMPANY: FORMER CONFORMED NAME: MITCHELL HUTCHINS INSTITUTIONAL SERIES DATE OF NAME CHANGE: 19980427 0001060517 S000002681 UBS Select Prime Institutional Fund C000007332 UBS Select Prime Institutional Fund SELXX 0001060517 S000002682 UBS Select Treasury Institutional Fund C000007334 UBS Select Treasury Institutional Fund SETXX 0001060517 S000002683 UBS Cash Reserves Fund C000007335 UBS Cash Reserves Fund 0001060517 S000002684 UBS Liquid Assets Fund C000007336 UBS Liquid Assets Fund 0001060517 S000018675 UBS Select Tax-Free Institutional Fund C000051798 UBS Select Tax-Free Institutional Fund STFXX 0001060517 S000018676 UBS Select Prime Preferred Fund C000051799 UBS Select Prime Preferred Fund SPPXX 0001060517 S000018677 UBS Select Treasury Preferred Fund C000051800 UBS Select Treasury Preferred Fund STPXX 0001060517 S000018678 UBS Select Tax-Free Preferred Fund C000051801 UBS Select Tax-Free Preferred Fund SFPXX 0001060517 S000018679 UBS Select Prime Investor Fund C000051802 UBS Select Prime Investor Fund SPIXX 0001060517 S000018680 UBS Select Treasury Investor Fund C000051803 UBS Select Treasury Investor Fund STRXX 0001060517 S000018681 UBS Select Tax-Free Investor Fund C000051804 UBS Select Tax-Free Investor Fund SFRXX 0001060517 S000023599 UBS Select Prime Capital Fund C000069431 UBS Select Prime Capital Fund 0001060517 S000023600 UBS Select Treasury Capital Fund C000069432 UBS Select Treasury Capital Fund 0001060517 S000023601 UBS Select Tax-Free Capital Fund C000069433 UBS Select Tax-Free Capital Fund 485BPOS 1 a13-19402_1485bpos.htm 485BPOS

 

As filed with the Securities and Exchange Commission on September 18, 2013

 

1933 Act:  Registration No.  333-52965

1940 Act:   Registration No. 811-08767

 

 

 

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

 

FORM N-1A

 

REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933  x

 

Pre-Effective Amendment No. o
Post-Effective Amendment No.  37
x

 

REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940 x

 

Amendment No. 38 x

 

UBS MONEY SERIES

[Exact Name of Registrant as Specified in Charter]

1285 Avenue of the Americas
New York, New York  10019-6028

(Address of Principal Executive Offices)

 

Registrant’s telephone number, including area code:  (212) 821-3000

 

MARK F. KEMPER, ESQ.
UBS Global Asset Management (Americas) Inc.
1285 Avenue of the Americas
New York, New York  10019-6028

(Name and Address of Agent for Service)

 

Copies to:
JACK W. MURPHY, ESQ.
Dechert LLP
1775 I Street, N.W.
Washington, D.C.  20006

Telephone: (202) 261-3300

 

Approximate Date of Proposed Public Offering:  Effective Date of this Post-Effective Amendment.

 

It is proposed that this filing will become effective:

x          Immediately upon filing pursuant to Rule 485(b)

o            On                                 , pursuant to Rule 485(b)

o            60 days after filing pursuant to Rule 485(a)(1)

o            On                                 , pursuant to Rule 485(a)(1)

o            75 days after filing pursuant to Rule 485(a)(2)

o            On                                 , pursuant to Rule 485(a)(2)

 

If appropriate, check the following box:

 

o            This post-effective amendment designates a new effective date for a previously filed post-effective amendment.

 

Title of Securities Being Registered: Shares of Beneficial Interest of UBS Select Prime Institutional Fund, UBS Select Treasury Institutional Fund, UBS Select Tax-Free Institutional Fund, UBS Select Prime Preferred Fund, UBS Select Treasury Preferred Fund, UBS Select Tax-Free Preferred Fund, UBS Select Prime Investor Fund, UBS Select Treasury Investor Fund, UBS Select Tax-Free Investor Fund, UBS Select Prime Capital Fund, UBS Select Treasury Capital Fund, UBS Select Tax-Free Capital Fund, UBS Cash Reserves Fund and UBS Liquid Assets Fund.

 

 

 



 

SIGNATURES

 

Pursuant to the requirements of the Securities Act of 1933 and the Investment Company Act of 1940, the Registrant certifies that it meets all the requirements for effectiveness of this Post-Effective Amendment to its Registration Statement under Rule 485(b) under the Securities Act of 1933 and has duly caused this Post-Effective Amendment to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of New York and State of New York, on the 18th day of September, 2013.

 

 

 

UBS MONEY SERIES

 

 

 

 

By:

/s/ Keith A. Weller

 

 

Keith A. Weller

 

 

Vice President and Assistant Secretary

 

Pursuant to the requirements of the Securities Act of 1933, this Post-Effective Amendment has been signed below by the following persons in the capacities and on the dates indicated:

 

SIGNATURE

 

TITLE

 

DATE

 

 

 

 

 

/s/ Richard Q. Armstrong

 

Trustee and Chairman of the Board of Trustees

 

September 18, 2013

Richard Q. Armstrong*

 

 

 

 

 

 

 

 

 

/s/ Alan S. Bernikow

 

Trustee

 

September 18, 2013

Alan S. Bernikow*

 

 

 

 

 

 

 

 

 

/s/ Richard R. Burt

 

Trustee

 

September 18, 2013

Richard R. Burt*

 

 

 

 

 

 

 

 

 

/s/ Mark E. Carver

 

President

 

September 18, 2013

Mark E. Carver**

 

 

 

 

 

 

 

 

 

/s/ Thomas Disbrow

 

Vice President and Treasurer

 

September 18, 2013

Thomas Disbrow

 

 

 

 

 

 

 

 

 

/s/ Meyer Feldberg

 

Trustee

 

September 18, 2013

Meyer Feldberg*

 

 

 

 

 

 

 

 

 

/s/ Bernard H. Garil

 

Trustee

 

September 18, 2013

Bernard H. Garil*

 

 

 

 

 

 

 

 

 

/s/ Heather R. Higgins

 

Trustee

 

September 18, 2013

Heather R. Higgins*

 

 

 

 

 

 

 

 

 

/s/ Barry M. Mandinach

 

Trustee

 

September 18, 2013

Barry M. Mandinach***

 

 

 

 

 


*

Signatures affixed by Lisa R. Price pursuant to Powers of Attorney dated November 14, 2007 and incorporated by reference from Post-Effective Amendment No. 28 to the registration statement of PACE Select Advisors Trust, SEC File No. 33-87254, filed November 28, 2007.

 

 

**

Signature affixed by Lisa R. Price pursuant to Power of Attorney dated May 19, 2010 and incorporated by reference from Post-Effective Amendment No. 28 to the registration statement of the Registrant, SEC File No. 333-52965, filed June 24, 2010.

 

 

***

Signature affixed by Lisa R. Price pursuant to Power of Attorney dated July 20, 2010 and incorporated by reference from Post-Effective Amendment No. 29 to the registration statement of the Registrant, SEC File No. 333-52965, filed August 27, 2010.

 

C-1



 

SIGNATURES

 

Master Trust, on behalf of its series, Prime Master Fund, Treasury Master Fund and Tax-Free Master Fund, has duly caused this Post-Effective Amendment to the Registration Statement for UBS Money Series to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of New York and State of New York, on the 18th day of September, 2013.

 

 

 

 

MASTER TRUST, on behalf of its series, Prime Master Fund, Treasury Master Fund and Tax-Free Master Fund

 

 

 

 

 

 

By:

/s/ Keith A. Weller

 

 

 

Keith A. Weller

 

 

 

Vice President and Assistant Secretary

 

Pursuant to the requirements of the Securities Act of 1933, this Post-Effective Amendment for UBS Money Series has been signed below by the following persons in the capacities and on the dates indicated:

 

SIGNATURE

 

TITLE

 

DATE

 

 

 

 

 

/s/ Richard Q. Armstrong

 

Trustee and Chairman of the Board of Trustees

 

September 18, 2013

Richard Q. Armstrong*

 

 

 

 

 

 

 

 

 

/s/ Alan S. Bernikow

 

Trustee

 

September 18, 2013

Alan S. Bernikow*

 

 

 

 

 

 

 

 

 

/s/ Richard R. Burt

 

Trustee

 

September 18, 2013

Richard R. Burt*

 

 

 

 

 

 

 

 

 

/s/ Mark E. Carver

 

President

 

September 18, 2013

Mark E. Carver**

 

 

 

 

 

 

 

 

 

/s/ Thomas Disbrow

 

Vice President and Treasurer

 

September 18, 2013

Thomas Disbrow

 

 

 

 

 

 

 

 

 

/s/ Meyer Feldberg

 

Trustee

 

September 18, 2013

Meyer Feldberg*

 

 

 

 

 

 

 

 

 

/s/ Bernard H. Garil

 

Trustee

 

September 18, 2013

Bernard H. Garil*

 

 

 

 

 

 

 

 

 

/s/ Heather R. Higgins

 

Trustee

 

September 18, 2013

Heather R. Higgins*

 

 

 

 

 

 

 

 

 

/s/ Barry M. Mandinach

 

Trustee

 

September 18, 2013

Barry M. Mandinach***

 

 

 

 

 


*

Signatures affixed by Lisa R. Price pursuant to Powers of Attorney dated November 14, 2007 and incorporated by reference from Post-Effective Amendment No. 28 to the registration statement of PACE Select Advisors Trust, SEC File No. 33-87254, filed November 28, 2007.

**

Signature affixed by Lisa R. Price pursuant to Power of Attorney dated May 19, 2010 and incorporated by reference from Post-Effective Amendment No. 28 to the registration statement of the Registrant, SEC File No. 333-52965, filed June 24, 2010.

***

Signature affixed by Lisa R. Price pursuant to Power of Attorney dated July 20, 2010 and incorporated by reference from Post-Effective Amendment No. 29 to the registration statement of the Registrant, SEC File No. 333-52965, filed August 27, 2010.

 

C-2



 

Exhibit Index

 

EX-101.INS

 

XBRL Instance Document

 

 

 

EX-101.SCH

 

XBRL Taxonomy Extension Schema Document

 

 

 

EX-101.CAL

 

XBRL Taxonomy Extension Calculation Linkbase

 

 

 

EX-101.DEF

 

XBRL Taxonomy Extension Definition Linkbase

 

 

 

EX-101.LAB

 

XBRL Taxonomy Extension Labels Linkbase

 

 

 

EX-101.PRE

 

XBRL Taxonomy Extension Presentation Linkbase

 

C-3


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("UBS Global AM"), the fund reimburses UBS Global AM for its direct costs and expenses incurred in managing the fund's portfolio, which are included in "Management fees" above. The fund also reimburses UBS Global AM for its direct costs and expenses in administering the fund. UBS Global AM's direct costs for management and administration services exclude any costs attributable to overhead or any profit charge. Expense information has been restated to reflect current fees. The fund invests in securities through an underlying master fund, Prime Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Prime Master Fund, including management fees allocated from Prime Master Fund. Management fees are comprised of investment advisory and administration fees. "Other expenses" do not include miscellaneous expenses, such as trustee expenses, for which UBS Global Asset Management (Americas) Inc. ("UBS Global AM") reimburses the fund. These other expenses are expected to be less than 0.01% of the average daily net assets of the fund. The fund invests in securities through an underlying master fund, Treasury Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Treasury Master Fund, including management fees allocated from Treasury Master Fund. Management fees are comprised of investment advisory and administration fees. The fund invests in securities through an underlying master fund, Tax-Free Master Fund. This table reflects the direct expenses of the fund and its share of the expenses of Tax-Free Master Fund, including management fees allocated from Tax-Free Master Fund. Management fees are comprised of investment advisory and administration fees. The fund invests in securities through an underlying master fund, Prime Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Prime Master Fund, including management fees allocated from Prime Master Fund. Management fees are comprised of investment advisory and administration fees. "Other expenses" do not include miscellaneous expenses, such as trustee expenses, for which UBS Global Asset Management (Americas) Inc. ("UBS Global AM") reimburses the fund. These other expenses are expected to be less than 0.01% of the average daily net assets of the fund. The fund and UBS Global AM have entered into a written fee waiver agreement pursuant to which UBS Global AM is contractually obligated to waive its management fees so that the total ordinary operating expenses of the fund through August 31, 2014, do not exceed 0.14%. The fee waiver agreement may be terminated by the fund's board at any time and also will terminate automatically upon the expiration or termination of the fund's contract with UBS Global AM. The fund invests in securities through an underlying master fund, Treasury Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Treasury Master Fund, including management fees allocated from Treasury Master Fund. Management fees are comprised of investment advisory and administration fees. The fund invests in securities through an underlying master fund, Tax-Free Master Fund. This table reflects the direct expenses of the fund and its share of the expenses of Tax-Free Master Fund, including management fees allocated from Tax-Free Master Fund. Management fees are comprised of investment advisory and administration fees. The fund and UBS Global Asset Management (Americas) Inc. ("UBS Global AM") have entered into a written fee waiver/expense reimbursement agreement pursuant to which UBS Global AM is contractually obligated to waive its management fees and/or reimburse the fund so that the fund's operating expenses through August 31, 2014 (excluding interest expense, if any, and extraordinary items) would not exceed 0.50%. The fund has agreed to repay UBS Global AM for any waived fees/reimbursed expenses to the extent that it can do so over the three years following such waived fees/reimbursed expenses without causing the fund's expenses in any of those three years to exceed the expense cap. The fee waiver/expense reimbursement agreement may be terminated by the fund's board at any time and also will terminate automatically upon the expiration or termination of the fund's contract with UBS Global AM. Upon termination of the agreement, however, UBS Global AM's three year recoupment rights will survive. The fund invests in securities through an underlying master fund, Tax-Free Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Tax-Free Master Fund, including management fees allocated from Tax-Free Master Fund. Management fees are comprised of investment advisory and administration fees. The fund and UBS Global Asset Management (Americas) Inc. ("UBS Global AM") have entered into a written fee waiver/expense reimbursement agreement pursuant to which UBS Global AM is contractually obligated to waive its management fees and/or reimburse the fund, and to cause its affiliate UBS Global Asset Management (US) Inc. to waive its shareholder servicing fee, so that the fund's operating expenses through August 31, 2014 (excluding interest expense, if any, and extraordinary items) would not exceed 0.20%. The fund has agreed to repay UBS Global AM for any waived fees/reimbursed expenses to the extent that it can do so over the three years following such waived fees/reimbursed expenses without causing the fund's expenses in any of those three years to exceed the expense cap. The fee waiver/expense reimbursement agreement may be terminated by the fund's board at any time and also will terminate automatically upon the expiration or termination of the fund's contract with UBS Global AM. Upon termination of the agreement, however, UBS Global AM's three year recoupment rights will survive. UBS MONEY SERIES 485BPOS false 0001060517 2013-04-30 2013-08-28 2013-08-28 2013-08-28 UBS Cash Reserves Fund Example <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund&#8217;s operating expenses remain the same.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</font> </p> 78 243 422 942 ~ http://ubs.com/20130828/role/ScheduleExpenseExampleTransposed20003 column dei_LegalEntityAxis compact ck0001060517_S000002683Member row primary compact * ~ Fees and expenses of the fund <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">These tables describe the fees and expenses that you may pay if you buy and hold shares of the fund.</font> </p> 0.0000 0.0000 0.0033 0.0000 0.0043 0.0076 ~ http://ubs.com/20130828/role/ScheduleShareholderFees20001 column dei_LegalEntityAxis compact ck0001060517_S000002683Member row primary compact * ~ ~ http://ubs.com/20130828/role/ScheduleAnnualFundOperatingExpenses20002 column dei_LegalEntityAxis compact ck0001060517_S000002683Member row primary compact * ~ Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment) Shareholder fees (fees paid directly from your investment) Principal strategies <p align="left"><b><font size="2" style="font-family: Arial;"><br/> Principal investments<br/> </font></b><font size="2" style="font-family: Arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. To do this, the fund invests in a diversified portfolio of high quality money market instruments of governmental and private issuers.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Money market instruments generally are short-term debt obligations and similar securities. They also may include longer-term bonds that have variable interest rates or other special features that give them the financial characteristics of short-term debt. The fund invests in foreign money market instruments only if they are denominated in US dollars.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management process<br /> </font></b><font size="2" style="font-family: Arial;">UBS Global Asset Management (Americas) Inc. (&#8220;UBS Global AM&#8221;) acts as the fund&#8217;s investment advisor. As investment advisor, UBS Global AM makes the fund&#8217;s investment decisions. UBS Global AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions. UBS Global AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</font> </p> Principal risks <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. All investments carry a certain amount of risk, and the fund cannot guarantee that it will achieve its investment objective. Money market instruments generally have a low risk of loss, but they are not risk-free. The principal risks presented by an investment in the fund are:</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Credit risk:</font></b> <font size="2" style="font-family: Arial;">Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">US Government securities risk:</font></b> <font size="2" style="font-family: Arial;">There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity,</font><b><font size="2" style="font-family: Arial;"></font></b><font size="2" style="font-family: Arial;">such as Federal National Mortgage Association (&#8220;Fannie Mae&#8220;) or Federal Home Loan Corporation (&#8220;Freddie Mac&#8220;), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Interest rate risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments generally will fall when interest rates rise, and its yield will tend to lag behind prevailing rates.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Market risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the market value of the fund&#8217;s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund&#8217;s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic and political conditions in one country or geographic region could adversely impact market, economic and political conditions in other countries or regions.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Foreign investing risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments in foreign securities may fall due to adverse political, social and economic developments abroad. However, because the fund&#8217;s foreign investments must be denominated in US dollars, it generally is not subject to the risk of changes in currency valuations.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Liquidity risk:</font></b> <font size="2" style="font-family: Arial;">Although the fund invests in a diversified portfolio of high quality instruments, the fund&#8217;s investments may become less liquid as a result of market developments or adverse investor perception.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results.</font> </p> Money market instruments generally have a low risk of loss, but they are not risk-free. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Investment objective <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">To provide as high a level of current interest income as is consistent with maintaining liquidity and stability of principal.</font> </p> Performance <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><b><font size="2" style="font-family: Arial;">Risk/return bar chart and table<br/> </font></b><font size="2" style="font-family: Arial;">The following bar chart and table provide information about the fund&#8217;s performance and thus give some indication of the risks of an investment in the fund.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The bar chart shows how the fund&#8217;s performance has varied from year to year. The table that follows the bar chart shows the average annual returns over various time periods for the fund&#8217;s shares.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund&#8217;s past performance does not necessarily indicate how the fund will perform in the future.</font> </p> Total return 0.0081 0.0095 0.0281 0.0467 0.0484 0.0237 0.0020 0.0002 0.0001 0.0001 ~ http://ubs.com/20130828/role/ScheduleAnnualTotalReturnsBarChart20004 column dei_LegalEntityAxis compact ck0001060517_S000002683Member column rr_ProspectusShareClassAxis compact ck0001060517_C000007335Member row primary compact * ~ Best quarter 0.0123 2006-09-30 Worst quarter 0.0000 2011-03-31 Total return January 1 to June 30, 2013: 0.0000 2013-06-30 <p align="left"> <font style="font-family: Arial; font-size: small;"><br /> Total return January 1 to June 30, 2013: 0.00% (Actual total return was 0.0050%)<br /> Best quarter during years shown &#8212; 3Q 2006: 1.23%<br /> </font> <font style="font-family: Arial; font-size: small;">Worst quarters during years shown &#8212; 3Q 2009; 1Q, 2Q &amp; 3Q 2010; &amp; 1Q 2011: 0.00% (Actual total returns were 0.0024%)</font> </p> <p align="left"> <font size="2" style="font-family: Arial;">Updated performance information is available by contacting your Financial Advisor or by calling 1-888-793 8637 (Option #1).</font> </p> 0.0001 0.0052 0.0165 ~ http://ubs.com/20130828/role/ScheduleAverageAnnualReturnsTransposed20005 column dei_LegalEntityAxis compact ck0001060517_S000002683Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ The fund's past performance does not necessarily indicate how the fund will perform in the future. The following bar chart and table provide information about the fund's performance and thus give some indication of the risks of an investment in the fund. Average annual total returns (for the periods ended December 31, 2012) 1-888-793 8637 (Option #1) UBS Liquid Assets Fund Example <p align="left"><br/> <font size="2" style="font-family: Arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund&#8217;s operating expenses remain the same.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</font> </p> 12 39 68 154 ~ http://ubs.com/20130828/role/ScheduleExpenseExampleTransposed20010 column dei_LegalEntityAxis compact ck0001060517_S000002684Member row primary compact * ~ Fees and expenses of the fund <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">These tables describe the fees and expenses that you may pay if you buy and hold shares of the fund.</font> </p> 0.0000 0.0000 0.0004 0.0000 0.0008 0.0012 ~ http://ubs.com/20130828/role/ScheduleShareholderFees20008 column dei_LegalEntityAxis compact ck0001060517_S000002684Member row primary compact * ~ ~ http://ubs.com/20130828/role/ScheduleAnnualFundOperatingExpenses20009 column dei_LegalEntityAxis compact ck0001060517_S000002684Member row primary compact * ~ Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment) Shareholder fees (fees paid directly from your investment) Expense information has been restated to reflect current fees. Principal strategies <p align="left"><b><font size="2" style="font-family: Arial;"><br/> Principal investments<br/> </font></b><font size="2" style="font-family: Arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. To do this, the fund invests in a diversified portfolio of high quality money market instruments of governmental and private issuers.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Money market instruments generally are short-term debt obligations and similar securities. They also may include longer-term bonds that have variable interest rates or other special features that give them the financial characteristics of short-term debt. The fund invests in foreign money market instruments only if they are denominated in US dollars.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management process<br /> </font></b><font size="2" style="font-family: Arial;">UBS Global Asset Management (Americas) Inc. (&#8220;UBS Global AM&#8221;) acts as the fund&#8217;s investment advisor. As investment advisor, UBS Global AM makes the fund&#8217;s investment decisions. UBS Global AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions. UBS Global AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</font> </p> Principal risks <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">All investments carry a certain amount of risk, and the fund cannot guarantee that it will achieve its investment objective. While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Money market instruments generally have a low risk of loss, but they are not risk-free. The principal risks presented by an investment in the fund are:</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Credit risk:</font></b> <font size="2" style="font-family: Arial;">Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">US Government securities risk:</font></b> <font size="2" style="font-family: Arial;">There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (&#8220;Fannie Mae&#8221;) or Federal Home Loan Mortgage Corporation (&#8220;Freddie Mac&#8220;), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Interest rate risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments generally will fall when interest rates rise, and its yield will tend to lag behind prevailing rates.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Market risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the market value of the fund&#8217;s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund&#8217;s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic and political conditions in one country or geographic region could adversely impact market, economic and political conditions in other countries or regions.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Foreign investing risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments in foreign securities may fall due to adverse political, social and economic developments abroad. However, because the fund&#8217;s foreign investments must be denominated in US dollars, it generally is not subject to the risk of changes in currency valuations.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Liquidity risk:</font></b> <font size="2" style="font-family: Arial;">Although the fund invests in a diversified portfolio of high quality instruments, the fund&#8217;s investments may become less liquid as a result of market developments or adverse investor perception.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results.</font> </p> While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Investment objective <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">To provide as high a level of current interest income as is consistent with maintaining liquidity and stability of principal.</font> </p> Performance <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><b><font size="2" style="font-family: Arial;">Risk/return bar chart and table<br/> </font></b><font size="2" style="font-family: Arial;">The following bar chart and table provide information about the fund&#8217;s performance and thus give some indication of the risks of an investment in the fund.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The bar chart shows how the fund&#8217;s performance has varied from year to year. The table that follows the bar chart shows the average annual returns over various time periods for the fund&#8217;s shares.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund&#8217;s past performance does not necessarily indicate how the fund will perform in the future.</font> </p> Total return 0.0106 0.0126 0.0313 0.0501 0.0522 0.0273 0.0048 0.0021 0.0016 0.0013 ~ http://ubs.com/20130828/role/ScheduleAnnualTotalReturnsBarChart20011 column dei_LegalEntityAxis compact ck0001060517_S000002684Member column rr_ProspectusShareClassAxis compact ck0001060517_C000007336Member row primary compact * ~ Best quarter 0.0133 2006-12-31 Worst quarter 0.0003 2012-06-30 Total return January 1 to June 30, 2013: 0.0007 2013-06-30 <p align="left"> <font size="2" style="font-family: Arial;">Total return January 1 to June 30, 2013: 0.07%<br /> Best quarter during years shown &#8212; 4Q 2006: 1.33%<br /> Worst quarter during years shown &#8212; 2Q 2012: 0.03%</font> </p> <p align="left"> <font size="2" style="font-family: Arial;">Updated performance information is available by contacting your Financial Advisor or by calling 1-888-793 8637 (Option #1).</font> </p> 0.0013 0.0074 0.0192 ~ http://ubs.com/20130828/role/ScheduleAverageAnnualReturnsTransposed20012 column dei_LegalEntityAxis compact ck0001060517_S000002684Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ The fund's past performance does not necessarily indicate how the fund will perform in the future. The following bar chart and table provide information about the fund's performance and thus give some indication of the risks of an investment in the fund. Average annual total returns (for the periods ended December 31, 2012) 1-888-793 8637 (Option #1) UBS Select Prime Institutional Fund SELXX Example <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund&#8217;s operating expenses remain the same.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</font> </p> 18 58 101 230 ~ http://ubs.com/20130828/role/ScheduleExpenseExampleTransposed20017 column dei_LegalEntityAxis compact ck0001060517_S000002681Member row primary compact * ~ Fees and expenses of the fund <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">These tables describe the fees and expenses that you may pay if you buy and hold shares of the fund.</font> </p> 0.0000 0.0000 0.0018 0.0000 0.0000 0.0018 ~ http://ubs.com/20130828/role/ScheduleShareholderFees20015 column dei_LegalEntityAxis compact ck0001060517_S000002681Member row primary compact * ~ ~ http://ubs.com/20130828/role/ScheduleAnnualFundOperatingExpenses20016 column dei_LegalEntityAxis compact ck0001060517_S000002681Member row primary compact * ~ Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment) Shareholder fees (fees paid directly from your investment) The fund invests in securities through an underlying master fund, Prime Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Prime Master Fund, including management fees allocated from Prime Master Fund. Management fees are comprised of investment advisory and administration fees. Principal strategies <p align="left"><b><font size="2" style="font-family: Arial;"><br/> Principal investments<br/> </font></b><font size="2" style="font-family: Arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. The fund seeks to achieve its objective by investing in a diversified portfolio of high quality money market instruments of governmental and private issuers. These may include:</font> </p> <br/><ul style="FONT-SIZE: 10pt; MARGIN-LEFT: 16px"> <li> <font size="2" style="font-family: Arial;">short-term obligations of the US government and its agencies and instrumentalities;<br /> &#160;</font> </li> <li> <font size="2" style="font-family: Arial;">repurchase agreements;<br /> &#160;</font> </li> <li> <font size="2" style="font-family: Arial;">obligations of issuers in the financial services group of industries; and<br /> &#160;</font> </li> <li> <font size="2" style="font-family: Arial;">commercial paper, other corporate obligations and asset-backed securities.</font> </li> </ul> <br/><p align="left"> <font size="2" style="font-family: Arial;">Money market instruments generally are short-term debt obligations and similar securities. They also may include longer-term bonds that have variable interest rates or other special features that give them the financial characteristics of short-term debt. The fund invests in foreign money market instruments only if they are denominated in US dollars. The fund will, under normal circumstances, invest more than 25% of its total assets in the financial services group of industries.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management process<br /> </font></b><font size="2" style="font-family: Arial;">UBS Global Asset Management (Americas) Inc. (&#8220;UBS Global AM&#8221;) acts as the investment advisor. As investment advisor, UBS Global AM makes the fund&#8217;s investment decisions. UBS Global AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions. UBS Global AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</font> </p> Principal risks <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">All investments carry a certain amount of risk, and the fund cannot guarantee that it will achieve its investment objective. While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Money market instruments generally have a low risk of loss, but they are not risk-free. The principal risks presented by an investment in the fund are:</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Credit risk:</font></b> <font size="2" style="font-family: Arial;">Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Concentration risk:</font></b> <font size="2" style="font-family: Arial;">The fund will invest a significant portion of its assets in securities issued by companies in the financial services group of industries, including US banking, non-US banking, broker-dealers, insurance companies, finance companies (e.g., automobile finance) and related asset-backed securities. Accordingly, the fund will be more susceptible to developments that affect those industries than other funds that do not concentrate their investments.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Financial services sector risk:</font></b> <font size="2" style="font-family: Arial;">Investments of the fund in the financial services sector may be particularly affected by economic cycles, business developments, interest rate changes and regulatory changes.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Foreign investing risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments in foreign securities may fall due to adverse political, social and economic developments abroad. However, because the fund&#8217;s foreign investments must be denominated in US dollars, it generally is not subject to the risk of changes in currency valuations.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">US Government securities risk:</font></b> <font size="2" style="font-family: Arial;">There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (&#8220;Fannie Mae&#8221;) or Federal Home Loan Mortgage Corporation (&#8220;Freddie Mac&#8221;), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Market risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the market value of the fund&#8217;s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund&#8217;s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic and political conditions in one country or geographic region could adversely impact market, economic and political conditions in other countries or regions.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Interest rate risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments generally will fall when interest rates rise, and its yield will tend to lag behind prevailing rates.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Liquidity risk:</font></b> <font size="2" style="font-family: Arial;">Although the fund invests in a diversified portfolio of high quality instruments, the fund&#8217;s investments may become less liquid as a result of market developments or adverse investor perception.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results.</font> </p> While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Investment objective <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">Maximum current income consistent with liquidity and the preservation of capital.</font> </p> Performance <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><b><font size="2" style="font-family: Arial;">Risk/return bar chart and table<br/> </font></b><font size="2" style="font-family: Arial;">The following bar chart and table provide information about the fund&#8217;s performance and thus give some indication of the risks of an investment in the fund.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The bar chart shows how the fund&#8217;s performance has varied from year to year.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The table that follows the bar chart shows the average annual returns over the various time periods for the fund&#8217;s shares.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Performance shown in the bar chart and table for the periods through August 27, 2007 reflects that of the Institutional share class of the fund prior to its conversion into a feeder fund of Prime Master Fund.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund&#8217;s past performance does not necessarily indicate how the fund will perform in the future.</font> </p> Total return UBS Select Prime Institutional Fund Annual Total Returns 0.0108 0.0125 0.0311 0.0499 0.0522 0.0283 0.0044 0.0015 0.0013 0.0014 ~ http://ubs.com/20130828/role/ScheduleAnnualTotalReturnsBarChart20018 column dei_LegalEntityAxis compact ck0001060517_S000002681Member column rr_ProspectusShareClassAxis compact ck0001060517_C000007332Member row primary compact * ~ Best quarter 0.0132 2007-09-30 Worst quarter 0.0002 2011-09-30 Total return January 1 to June 30, 2013: 0.0003 2013-06-30 <p align="left"> <font size="2" style="font-family: Arial;">Total return January 1 to June 30, 2013: 0.03%<br /> Best quarter during years shown - 3Q 2007: 1.32%<br /> Worst quarter during years shown - 3Q 2011: 0.02%</font> </p> <p align="left"> <font size="2" style="font-family: Arial;">Updated performance information is available by contacting your Financial Advisor or by calling 1-888-793 8637 (Option #1).</font> </p> 0.0014 0.0073 0.0192 ~ http://ubs.com/20130828/role/ScheduleAverageAnnualReturnsTransposed20019 column dei_LegalEntityAxis compact ck0001060517_S000002681Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ The fund's past performance does not necessarily indicate how the fund will perform in the future. The following bar chart and table provide information about the fund's performance and thus give some indication of the risks of an investment in the fund. Average annual total returns (for the periods ended December 31, 2012) 1-888-793 8637 (Option #1) UBS Select Treasury Institutional Fund SETXX Example <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund&#8217;s operating expenses remain the same.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</font> </p> 18 58 101 230 ~ http://ubs.com/20130828/role/ScheduleExpenseExampleTransposed20024 column dei_LegalEntityAxis compact ck0001060517_S000002682Member row primary compact * ~ Principal risks <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">All investments carry a certain amount of risk, and the fund cannot guarantee that it will achieve its investment objective. While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Money market instruments generally have a low risk of loss, but they are not risk-free. The principal risks presented by an investment in the fund are:</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Credit risk:</font></b> <font size="2" style="font-family: Arial;">Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">US Government securities risk:</font></b> <font size="2" style="font-family: Arial;">There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (&#8220;Fannie Mae&#8221;) or Federal Home Loan Mortgage Corporation (&#8220;Freddie Mac&#8221;), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Market risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the market value of the fund&#8217;s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund&#8217;s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic and political conditions in one country or geographic region could adversely impact market, economic and political conditions in other countries or regions.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Interest rate risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments generally will fall when interest rates rise, and its yield will tend to lag behind prevailing rates.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Liquidity risk:</font></b> <font size="2" style="font-family: Arial;">Although the fund invests in securities issued by the US Treasury and in related repurchase agreements, the fund&#8217;s investments may become less liquid as a result of market developments or adverse investor perception.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results.</font> </p> While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Principal strategies <p align="left"><b><font size="2" style="font-family: Arial;"><br/> Principal investments<br/> </font></b><font size="2" style="font-family: Arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. Under normal circumstances, the fund seeks to achieve its objective by investing at least 80% of its net assets (plus the amount of any borrowing for investment purposes) in securities issued by the US Treasury and in related repurchase agreements. However, under normal circumstances the fund expects to invest substantially all of its assets in securities issued by the US Treasury and in related repurchase agreements. The fund may invest a significant percentage of its assets in repurchase agreements. Repurchase agreements involve transactions in which the fund purchases securities issued by the US Treasury and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of interest. While income earned by the fund&#8217;s direct investments in securities issued by the US Treasury may qualify for favorable state and local income taxation, income related to repurchase agreements may not be so advantaged. Investing in repurchase agreements may permit the fund quickly to take advantage of increases in short-term rates.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Money market instruments generally are short-term debt obligations and similar securities. They also may include longer-term bonds that have variable interest rates or other special features that give them the financial characteristics of short-term debt.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management process<br /> </font></b><font size="2" style="font-family: Arial;">UBS Global Asset Management (Americas) Inc. (&#8220;UBS Global AM&#8221;) acts as the investment advisor. As investment advisor, UBS Global AM makes the fund&#8217;s investment decisions. UBS Global AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">UBS Global AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</font> </p> Fees and expenses of the fund <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">These tables describe the fees and expenses that you may pay if you buy and hold shares of the fund.</font> </p> 0.0000 0.0000 0.0018 0.0000 0.0000 0.0018 ~ http://ubs.com/20130828/role/ScheduleShareholderFees20022 column dei_LegalEntityAxis compact ck0001060517_S000002682Member row primary compact * ~ ~ http://ubs.com/20130828/role/ScheduleAnnualFundOperatingExpenses20023 column dei_LegalEntityAxis compact ck0001060517_S000002682Member row primary compact * ~ Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment) Shareholder fees (fees paid directly from your investment) The fund invests in securities through an underlying master fund, Treasury Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Treasury Master Fund, including management fees allocated from Treasury Master Fund. Management fees are comprised of investment advisory and administration fees. Performance <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><b><font size="2" style="font-family: Arial;">Risk/return bar chart and table<br/> </font></b><font size="2" style="font-family: Arial;">The following bar chart and table provide information about the fund&#8217;s performance and thus give some indication of the risks of an investment in the fund.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The bar chart shows how the fund&#8217;s performance has varied from year to year.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The table that follows the bar chart shows the average annual returns over the various time periods for the fund&#8217;s shares.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Performance shown in the bar chart and table for the periods through August 27, 2007 reflects that of the Institutional share class of the fund prior to its conversion into a feeder fund of Treasury Master Fund.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund&#8217;s past performance does not necessarily indicate how the fund will perform in the future.</font> </p> Total return (2005 was the fund's first full calendar year of operations) UBS Select Treasury Insistutional Fund Annual Total Returns 0.0297 0.0483 0.0479 0.0158 0.0009 0.0002 0.0001 0.0001 ~ http://ubs.com/20130828/role/ScheduleAnnualTotalReturnsBarChart20025 column dei_LegalEntityAxis compact ck0001060517_S000002682Member column rr_ProspectusShareClassAxis compact ck0001060517_C000007334Member row primary compact * ~ Best quarter 0.0129 2006-12-31 Worst quarter 0.0000 2011-06-30 Total return January 1 to June 30, 2013: 0.0000 2013-06-30 <p align="left"> <font size="2" style="font-family: Arial;">Total return January 1 to June 30, 2013: 0.00% (Actual total return was 0.0050%)<br /> Best quarter during years shown - 4Q 2006: 1.29%<br /> Worst quarter during years shown - 2Q 2011: 0.00%</font><b><font size="2" style="font-family: Arial;"></font></b><font size="2" style="font-family: Arial;">(Actual total return was 0.0025%)</font> </p> <p align="left"> <font size="2" style="font-family: Arial;">Updated performance information is available by contacting your Financial Advisor or by calling 1-888-793 8637 (Option #1).</font> </p> 0.0001 0.0034 0.0172 2004-03-23 ~ http://ubs.com/20130828/role/ScheduleAverageAnnualReturnsTransposed20026 column dei_LegalEntityAxis compact ck0001060517_S000002682Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ The fund's past performance does not necessarily indicate how the fund will perform in the future. The following bar chart and table provide information about the fund's performance and thus give some indication of the risks of an investment in the fund. Average annual total returns (for the periods ended December 31, 2012) 1-888-793 8637 (Option #1) Investment objective <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">Maximum current income consistent with liquidity and the preservation of capital.</font> </p> UBS Select Tax-Free Institutional Fund STFXX Example <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund&#8217;s operating expenses remain the same.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</font> </p> 18 58 101 230 ~ http://ubs.com/20130828/role/ScheduleExpenseExampleTransposed20031 column dei_LegalEntityAxis compact ck0001060517_S000018675Member row primary compact * ~ Principal risks <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">All investments carry a certain amount of risk, and the fund cannot guarantee that it will achieve its investment objective. While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Money market instruments generally have a low risk of loss, but they are not risk-free. The principal risks presented by an investment in the fund are:</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Credit risk:</font></b> <font size="2" style="font-family: Arial;">Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Interest rate risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments generally will fall when interest rates rise, and its yield will tend to lag behind prevailing rates.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Market risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the market value of the fund&#8217;s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund&#8217;s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic and political conditions in one country or geographic region could adversely impact market, economic and political conditions in other countries or regions.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Liquidity risk:</font></b> <font size="2" style="font-family: Arial;">Although the fund invests in a diversified portfolio of high quality instruments, the fund&#8217;s investments may become less liquid as a result of market developments or adverse investor perception.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Municipal securities risk:</font></b> <font size="2" style="font-family: Arial;">Municipal securities are subject to interest rate and credit risks. The ability of a municipal issuer to make payments and the value of municipal securities can be affected by uncertainties in the municipal securities market. Such uncertainties could cause increased volatility in the municipal securities market and could negatively impact the fund&#8217;s net asset value and/or the distributions paid by the fund. Municipalities continue to experience difficulties in the current economic and political environment.</font> </p> While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Principal strategies <p align="left"><b><font size="2" style="font-family: Arial;"><br/> Principal investments<br/> </font></b><font size="2" style="font-family: Arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. The fund seeks to achieve its objective by investing in a diversified portfolio of high quality, municipal money market instruments.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Under normal circumstances, the fund will invest at least 80% of its net assets (plus the amount of any borrowing for investment purposes) in investments, the income from which is exempt from federal income tax. Investments that are subject to the alternative minimum tax are not counted towards satisfying the 80% test in the foregoing sentence. Under normal circumstances, the fund may invest only up to 20% of its net assets in municipal securities that pay interest that is an item of tax preference for purposes of the alternative minimum tax.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Money market instruments generally are short-term debt obligations and similar securities. They also may include longer-term bonds that have variable interest rates or other special features that give them the financial characteristics of short-term debt.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management process<br /> </font></b><font size="2" style="font-family: Arial;">UBS Global Asset Management (Americas) Inc. (&#8220;UBS Global AM&#8221;) acts as the investment advisor. As investment advisor, UBS Global AM makes the fund&#8217;s investment decisions. UBS Global AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</font> </p> Fees and expenses of the fund <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">These tables describe the fees and expenses that you may pay if you buy and hold shares of the fund.</font> </p> 0.0000 0.0000 0.0018 0.0000 0.0000 0.0018 ~ http://ubs.com/20130828/role/ScheduleShareholderFees20029 column dei_LegalEntityAxis compact ck0001060517_S000018675Member row primary compact * ~ ~ http://ubs.com/20130828/role/ScheduleAnnualFundOperatingExpenses20030 column dei_LegalEntityAxis compact ck0001060517_S000018675Member row primary compact * ~ Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment) Shareholder fees (fees paid directly from your investment) The fund invests in securities through an underlying master fund, Tax-Free Master Fund. This table reflects the direct expenses of the fund and its share of the expenses of Tax-Free Master Fund, including management fees allocated from Tax-Free Master Fund. Management fees are comprised of investment advisory and administration fees. Performance <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><b><font size="2" style="font-family: Arial;">Risk/return bar chart and table<br/> </font></b><font size="2" style="font-family: Arial;">The following bar chart and table provide information about the fund&#8217;s performance and thus give some indication of the risks of an investment in the fund.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The bar chart shows how the fund&#8217;s performance has varied from year to year.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The table that follows the bar chart shows the average annual returns over the various time periods for the fund&#8217;s shares.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund&#8217;s past performance does not necessarily indicate how the fund will perform in the future.</font> </p> Total return (2008 was the fund's first full calendar year of operations) UBS Select Tax-Free Institutional Fund Annual Total Returns 0.0194 0.0019 0.0010 0.0004 0.0002 ~ http://ubs.com/20130828/role/ScheduleAnnualTotalReturnsBarChart20032 column dei_LegalEntityAxis compact ck0001060517_S000018675Member column rr_ProspectusShareClassAxis compact ck0001060517_C000051798Member row primary compact * ~ Best quarter 0.0060 2008-03-31 Worst quarter 0.0000 2011-09-30 Total return January 1 to June 30, 2013: 0.0001 2013-06-30 <p align="left"> <font size="2" style="font-family: Arial;">Total return January 1 to June 30, 2013: 0.01%<br /> Best quarter during years shown - 1Q 2008: 0.60%<br /> </font> <font size="2" style="font-family: Arial;">Worst quarter during years shown - 3Q 2011: 0.00%</font><b><font size="2" style="font-family: Arial;"></font></b><font size="2" style="font-family: Arial;">(Actual total return was 0.0025%)</font> </p> <p align="left"> <font size="2" style="font-family: Arial;">Updated performance information is available by contacting your Financial Advisor or by calling 1-888-793 8637 (Option #1).</font> </p> 0.0002 0.0046 0.0065 2007-08-28 ~ http://ubs.com/20130828/role/ScheduleAverageAnnualReturnsTransposed20033 column dei_LegalEntityAxis compact ck0001060517_S000018675Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ The fund's past performance does not necessarily indicate how the fund will perform in the future. The following bar chart and table provide information about the fund's performance and thus give some indication of the risks of an investment in the fund. Average annual total returns (for the periods ended December 31, 2012) 1-888-793 8637 (Option #1) Investment objective <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">Maximum current income exempt from federal income tax consistent with liquidity and the preservation of capital.</font> </p> UBS Select Prime Preferred Fund SPPXX Example <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund&#8217;s operating expenses remain the same.*</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</font> </p> 14 54 97 226 ~ http://ubs.com/20130828/role/ScheduleExpenseExampleTransposed20038 column dei_LegalEntityAxis compact ck0001060517_S000018676Member row primary compact * ~ <p align="left"> <font size="1" style="font-family: Arial;">*&#160;&#160;&#160;&#160; Except that the expenses reflect the effects of the fund&#8217;s fee waiver agreement for the first year only.</font> </p> Principal risks <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">All investments carry a certain amount of risk, and the fund cannot guarantee that it will achieve its investment objective. While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Money market instruments generally have a low risk of loss, but they are not risk-free. The principal risks presented by an investment in the fund are:</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Credit risk:</font></b> <font size="2" style="font-family: Arial;">Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Concentration risk:</font></b> <font size="2" style="font-family: Arial;">The fund will invest a significant portion of its assets in securities issued by companies in the financial services group of industries, including US banking, non-US banking, broker-dealers, insurance companies, finance companies (</font><i><font size="2" style="font-family: Arial;">e.g.</font></i><font size="2" style="font-family: Arial;">, automobile finance) and related asset-backed securities. Accordingly, the fund will be more susceptible to developments that affect those industries than other funds that do not concentrate their investments.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Financial services sector risk:</font></b> <font size="2" style="font-family: Arial;">Investments of the fund in the financial services sector may be particularly affected by economic cycles, business developments, interest rate changes and regulatory changes.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Foreign investing risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments in foreign securities may fall due to adverse political, social and economic developments abroad. However, because the fund&#8217;s foreign investments must be denominated in US dollars, it generally is not subject to the risk of changes in currency valuations.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">US Government securities risk:</font></b> <font size="2" style="font-family: Arial;">There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (&#8220;Fannie Mae&#8221;) or Federal Home Loan Mortgage Corporation (&#8220;Freddie Mac&#8221;), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Market risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the market value of the fund&#8217;s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund&#8217;s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic and political conditions in one country or geographic region could adversely impact market, economic and political conditions in other countries or regions.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Interest rate risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments generally will fall when interest rates rise, and its yield will tend to lag behind prevailing rates.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Liquidity risk:</font></b> <font size="2" style="font-family: Arial;">Although the fund invests in a diversified portfolio of high quality instruments, the fund&#8217;s investments may become less liquid as a result of market developments or adverse investor perception.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results.</font> </p> While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Principal strategies <div align="left"><b><font size="2" style="font-family: Arial;"><br/> Principal investments</font></b> </div> <br/><div align="left"> <font size="2" style="font-family: Arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. The fund seeks to achieve its objective by investing in a diversified portfolio of high quality money market instruments of governmental and private issuers. These may include:</font> </div> <br/><ul style="FONT-SIZE: 10pt; MARGIN-LEFT: 16px"> <li> <font size="2" style="font-family: Arial;">short-term obligations of the US government and its agencies and instrumentalities;</font><br /> &#160; </li> <li> <font size="2" style="font-family: Arial;">repurchase agreements;</font><br /> &#160; </li> <li> <font size="2" style="font-family: Arial;">obligations of issuers in the financial services group of industries; and</font><br /> &#160; </li> <li> <font size="2" style="font-family: Arial;">commercial paper, other corporate obligations and asset-backed securities.</font> </li> </ul> <br/><p align="left"> <font size="2" style="font-family: Arial;">Money market instruments generally are short-term debt obligations and similar securities. They also may include longer-term bonds that have variable interest rates or other special features that give them the financial characteristics of short-term debt. The fund invests in foreign money market instruments only if they are denominated in US dollars. The fund will, under normal circumstances, invest more than 25% of its total assets in the financial services group of industries.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management process<br /> </font></b><font size="2" style="font-family: Arial;">UBS Global Asset Management (Americas) Inc. (&#8220;UBS Global AM&#8221;) acts as the investment advisor. As investment advisor, UBS Global AM makes the fund&#8217;s investment decisions. UBS Global AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions. UBS Global AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</font> </p> Fees and expenses of the fund <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">These tables describe the fees and expenses that you may pay if you buy and hold shares of the fund.</font> </p> 0.0000 0.0000 0.0018 0.0000 0.0000 0.0018 -0.0004 0.0014 ~ http://ubs.com/20130828/role/ScheduleShareholderFees20036 column dei_LegalEntityAxis compact ck0001060517_S000018676Member row primary compact * ~ ~ http://ubs.com/20130828/role/ScheduleAnnualFundOperatingExpenses20037 column dei_LegalEntityAxis compact ck0001060517_S000018676Member row primary compact * ~ Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment) Shareholder fees (fees paid directly from your investment) The fund invests in securities through an underlying master fund, Prime Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Prime Master Fund, including management fees allocated from Prime Master Fund. Management fees are comprised of investment advisory and administration fees. 2014-08-31 Performance <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><b><font size="2" style="font-family: Arial;">Risk/return bar chart and table<br/> </font></b><font size="2" style="font-family: Arial;">The following bar chart and table provide information about the fund&#8217;s performance and thus give some indication of the risks of an investment in the fund.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The bar chart shows how the fund&#8217;s performance has varied from year to year.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The table that follows the bar chart shows the average annual returns over the various time periods for the fund&#8217;s shares.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund&#8217;s past performance does not necessarily indicate how the fund will perform in the future.</font> </p> Total return (2008 was the fund's first full calendar year of operations) UBS Select Prime Preferred Fund Annual Total Returns 0.0288 0.0049 0.0019 0.0017 0.0018 ~ http://ubs.com/20130828/role/ScheduleAnnualTotalReturnsBarChart20039 column dei_LegalEntityAxis compact ck0001060517_S000018676Member column rr_ProspectusShareClassAxis compact ck0001060517_C000051799Member row primary compact * ~ Best quarter 0.0095 2008-03-31 Worst quarter 0.0003 2011-09-30 Total return January 1 to June 30, 2013: 0.0005 2013-06-30 <p align="left"> <font size="2" style="font-family: Arial;">Total return January 1 to June 30, 2013: 0.05%<br /> Best quarter during years shown &#8211; 1Q 2008: 0.95%<br /> Worst quarter during years shown &#8211; 3Q 2011: 0.03%</font> </p> <p align="left"> <font size="2" style="font-family: Arial;">Updated performance information is available by contacting your Financial Advisor or by calling 1-888-793 8637 (Option #1).</font> </p> 0.0018 0.0078 0.0105 2007-08-28 ~ http://ubs.com/20130828/role/ScheduleAverageAnnualReturnsTransposed20040 column dei_LegalEntityAxis compact ck0001060517_S000018676Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ The fund's past performance does not necessarily indicate how the fund will perform in the future. The following bar chart and table provide information about the fund's performance and thus give some indication of the risks of an investment in the fund. Average annual total returns (for the periods ended December 31, 2012) 1-888-793 8637 (Option #1) Investment objective <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">Maximum current income consistent with liquidity and the preservation of capital.</font> </p> UBS Select Treasury Preferred Fund STPXX Example <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund&#8217;s operating expenses remain the same.*</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</font> </p> 14 54 97 226 ~ http://ubs.com/20130828/role/ScheduleExpenseExampleTransposed20045 column dei_LegalEntityAxis compact ck0001060517_S000018677Member row primary compact * ~ <font size="1" style="font-family: Arial;"><br /> *&#160;&#160;&#160;&#160; Except that the expenses reflect the effects of the fund&#8217;s fee waiver agreement for the first year only.</font> Principal risks <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">All investments carry a certain amount of risk, and the fund cannot guarantee that it will achieve its investment objective. While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Money market instruments generally have a low risk of loss, but they are not risk-free. The principal risks presented by an investment in the fund are:</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Credit risk:</font></b> <font size="2" style="font-family: Arial;">Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">US Government securities risk:</font></b> <font size="2" style="font-family: Arial;">There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (&#8220;Fannie Mae&#8221;) or Federal Home Loan Mortgage Corporation (&#8220;Freddie Mac&#8221;), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Market risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the market value of the fund&#8217;s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund&#8217;s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic and political conditions in one country or geographic region could adversely impact market, economic and political conditions in other countries or regions.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Interest rate risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments generally will fall when interest rates rise, and its yield will tend to lag behind prevailing rates.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Liquidity risk:</font></b> <font size="2" style="font-family: Arial;">Although the fund invests in securities issued by the US Treasury and in related repurchase agreements, the fund&#8217;s investments may become less liquid as a result of market developments or adverse investor perception.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results.</font> </p> While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Principal strategies <p align="left"><b><font size="2" style="font-family: Arial;"><br/> Principal investments<br/> </font></b><font size="2" style="font-family: Arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. Under normal circumstances, the fund seeks to achieve its objective by investing at least 80% of its net assets (plus the amount of any borrowing for investment purposes) in securities issued by the US Treasury and in related repurchase agreements. However, under normal circumstances the fund expects to invest substantially all of its assets in securities issued by the US Treasury and in related repurchase agreements. The fund may invest a significant percentage of its assets in repurchase agreements. Repurchase agreements involve transactions in which the fund purchases securities issued by the US Treasury and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of interest. While income earned by the fund&#8217;s direct investments in securities issued by the US Treasury may qualify for favorable state and local income taxation, income related to repurchase agreements may not be so advantaged. Investing in repurchase agreements may permit the fund quickly to take advantage of increases in short-term rates.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Money market instruments generally are short-term debt obligations and similar securities. They also may include longer-term bonds that have variable interest rates or other special features that give them the financial characteristics of short-term debt.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management process<br /> </font></b><font size="2" style="font-family: Arial;">UBS Global Asset Management (Americas) Inc. (&#8220;UBS Global AM&#8221;) acts as the investment advisor. As investment advisor, UBS Global AM makes the fund&#8217;s investment decisions. UBS Global AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">UBS Global AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</font> </p> Fees and expenses of the fund <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">These tables describe the fees and expenses that you may pay if you buy and hold shares of the fund.</font> </p> 0.0000 0.0000 0.0018 0.0000 0.0000 0.0018 -0.0004 0.0014 ~ http://ubs.com/20130828/role/ScheduleShareholderFees20043 column dei_LegalEntityAxis compact ck0001060517_S000018677Member row primary compact * ~ ~ http://ubs.com/20130828/role/ScheduleAnnualFundOperatingExpenses20044 column dei_LegalEntityAxis compact ck0001060517_S000018677Member row primary compact * ~ Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment) Shareholder fees (fees paid directly from your investment) The fund invests in securities through an underlying master fund, Treasury Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Treasury Master Fund, including management fees allocated from Treasury Master Fund. Management fees are comprised of investment advisory and administration fees. 2014-08-31 Performance <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><b><font size="2" style="font-family: Arial;">Risk/return bar chart and table<br/> </font></b><font size="2" style="font-family: Arial;">The following bar chart and table provide information about the fund&#8217;s performance and thus give some indication of the risks of an investment in the fund.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The bar chart shows how the fund&#8217;s performance has varied from year to year.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The table that follows the bar chart shows the average annual returns over the various time periods for the fund&#8217;s shares.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund&#8217;s past performance does not necessarily indicate how the fund will perform in the future.</font> </p> Total return (2008 was the fund's first full calendar year of operations) UBS Select Treasury Preferred Fund Annual Total Returns 0.0162 0.0013 0.0006 0.0001 0.0002 ~ http://ubs.com/20130828/role/ScheduleAnnualTotalReturnsBarChart20046 column dei_LegalEntityAxis compact ck0001060517_S000018677Member column rr_ProspectusShareClassAxis compact ck0001060517_C000051800Member row primary compact * ~ Best quarter 0.0062 2008-03-31 Worst quarter 0.0000 2011-06-30 Total return January 1 to June 30, 2013: 0.0000 2013-06-30 <p align="left"> <font size="2" style="font-family: Arial;">Total return January 1 to June 30, 2013: 0.00% (Actual total return was 0.0050%)<br /> Best quarter during years shown &#8211; 1Q 2008: 0.62%<br /> Worst quarter during years shown &#8211; 2Q 2011: 0.00%</font><b><font size="2" style="font-family: Arial;"></font></b><font size="2" style="font-family: Arial;">(Actual total return was 0.0025%)</font> </p> <p align="left"> <font size="2" style="font-family: Arial;">Updated performance information is available by contacting your Financial Advisor or by calling 1-888-793 8637 (Option #1).</font> </p> 0.0002 0.0037 0.0062 2007-08-28 ~ http://ubs.com/20130828/role/ScheduleAverageAnnualReturnsTransposed20047 column dei_LegalEntityAxis compact ck0001060517_S000018677Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ The fund's past performance does not necessarily indicate how the fund will perform in the future. The following bar chart and table provide information about the fund's performance and thus give some indication of the risks of an investment in the fund. Average annual total returns (for the periods ended December 31, 2012) 1-888-793 8637 (Option #1) Investment objective <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">Maximum current income consistent with liquidity and the preservation of capital.</font> </p> UBS Select Tax-Free Preferred Fund SFPXX Example <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund&#8217;s operating expenses remain the same.*</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</font> </p> 14 54 97 226 ~ http://ubs.com/20130828/role/ScheduleExpenseExampleTransposed20052 column dei_LegalEntityAxis compact ck0001060517_S000018678Member row primary compact * ~ <p align="left"> <font size="1" style="font-family: Arial;">*&#160;&#160;&#160;&#160; Except that the expenses reflect the effects of the fund&#8217;s fee waiver agreement for the first year only.</font> </p> Principal risks <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">All investments carry a certain amount of risk, and the fund cannot guarantee that it will achieve its investment objective. While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Money market instruments generally have a low risk of loss, but they are not risk-free. The principal risks presented by an investment in the fund are:</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Credit risk:</font></b> <font size="2" style="font-family: Arial;">Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Interest rate risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments generally will fall when interest rates rise, and its yield will tend to lag behind prevailing rates.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Market risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the market value of the fund&#8217;s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund&#8217;s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic and political conditions in one country or geographic region could adversely impact market, economic and political conditions in other countries or regions.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Liquidity risk:</font></b> <font size="2" style="font-family: Arial;">Although the fund invests in a diversified portfolio of high quality instruments, the fund&#8217;s investments may become less liquid as a result of market developments or adverse investor perception.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Municipal securities risk:</font></b> <font size="2" style="font-family: Arial;">Municipal securities are subject to interest rate and credit risks. The ability of a municipal issuer to make payments and the value of municipal securities can be affected by uncertainties in the municipal securities market. Such uncertainties could cause increased volatility in the municipal securities market and could negatively impact the fund&#8217;s net asset value and/or the distributions paid by the fund. Municipalities continue to experience difficulties in the current economic and political environment.</font> </p> While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Principal strategies <p align="left"><b><font size="2" style="font-family: Arial;"><br/> Principal investments<br/> </font></b><font size="2" style="font-family: Arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. The fund seeks to achieve its objective by investing in a diversified portfolio of high quality, municipal money market instruments.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Under normal circumstances, the fund will invest at least 80% of its net assets (plus the amount of any borrowing for investment purposes) in investments, the income from which is exempt from federal income tax. Investments that are subject to the alternative minimum tax are not counted towards satisfying the 80% test in the foregoing sentence. Under normal circumstances, the fund may invest only up to 20% of its net assets in municipal securities that pay interest that is an item of tax preference for purposes of the alternative minimum tax.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Money market instruments generally are short-term debt obligations and similar securities. They also may include longer-term bonds that have variable interest rates or other special features that give them the financial characteristics of short-term debt.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management process<br /> </font></b><font size="2" style="font-family: Arial;">UBS Global Asset Management (Americas) Inc. (&#8220;UBS Global AM&#8221;) acts as the investment advisor. As investment advisor, UBS Global AM makes the fund&#8217;s investment decisions. UBS Global AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</font> </p> Fees and expenses of the fund <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">These tables describe the fees and expenses that you may pay if you buy and hold shares of the fund.</font> </p> 0.0000 0.0000 0.0018 0.0000 0.0000 0.0018 -0.0004 0.0014 ~ http://ubs.com/20130828/role/ScheduleShareholderFees20050 column dei_LegalEntityAxis compact ck0001060517_S000018678Member row primary compact * ~ ~ http://ubs.com/20130828/role/ScheduleAnnualFundOperatingExpenses20051 column dei_LegalEntityAxis compact ck0001060517_S000018678Member row primary compact * ~ Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment) Shareholder fees (fees paid directly from your investment) The fund invests in securities through an underlying master fund, Tax-Free Master Fund. This table reflects the direct expenses of the fund and its share of the expenses of Tax-Free Master Fund, including management fees allocated from Tax-Free Master Fund. Management fees are comprised of investment advisory and administration fees. 2014-08-31 Performance <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><b><font size="2" style="font-family: Arial;">Risk/return bar chart and table<br/> </font></b><font size="2" style="font-family: Arial;">The following bar chart and table provide information about the fund&#8217;s performance and thus give some indication of the risks of an investment in the fund.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The bar chart shows how the fund&#8217;s performance has varied from year to year.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The table that follows the bar chart shows the average annual returns over the various time periods for the fund&#8217;s shares.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund&#8217;s past performance does not necessarily indicate how the fund will perform in the future.</font> </p> Total return (2008 was the fund's first full calendar year of operations) UBS Select Tax-Free Preferred Fund Annual Total Returns 0.0197 0.0021 0.0014 0.0006 0.0004 ~ http://ubs.com/20130828/role/ScheduleAnnualTotalReturnsBarChart20053 column dei_LegalEntityAxis compact ck0001060517_S000018678Member column rr_ProspectusShareClassAxis compact ck0001060517_C000051801Member row primary compact * ~ Best quarter 0.0061 2008-03-31 Worst quarter 0.0000 2011-12-31 Total return January 1 to June 30, 2013: 0.0001 2013-06-30 <p align="left"> <font size="2" style="font-family: Arial;">Total return January 1 to June 30, 2013: 0.01%<br /> Best quarter during years shown &#8211; 1Q 2008: 0.61%<br /> </font> <font size="2" style="font-family: Arial;">Worst quarter during years shown &#8211; 4Q 2011: 0.00%</font><b><font size="2" style="font-family: Arial;"></font></b><font size="2" style="font-family: Arial;">(Actual total return was 0.0042%)</font> </p> <p align="left"> <font size="2" style="font-family: Arial;">Updated performance information is available by contacting your Financial Advisor or by calling 1-888-793 8637 (Option #1).</font> </p> 0.0004 0.0048 0.0068 2007-08-28 ~ http://ubs.com/20130828/role/ScheduleAverageAnnualReturnsTransposed20054 column dei_LegalEntityAxis compact ck0001060517_S000018678Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ The fund's past performance does not necessarily indicate how the fund will perform in the future. The following bar chart and table provide information about the fund's performance and thus give some indication of the risks of an investment in the fund. Average annual total returns (for the periods ended December 31, 2012) 1-888-793 8637 (Option #1) Investment objective <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">Maximum current income exempt from federal income tax consistent with liquidity and the preservation of capital.</font> </p> UBS Select Prime Investor Fund SPIXX Example <p align="left"><br/> <font size="2" style="font-family: Arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund&#8217;s operating expenses remain the same.*</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</font> </p> 51 182 325 740 ~ http://ubs.com/20130828/role/ScheduleExpenseExampleTransposed20059 column dei_LegalEntityAxis compact ck0001060517_S000018679Member row primary compact * ~ <table cellspacing="0" cellpadding="0" border="0"> <tr> <td valign="top" nowrap="nowrap"> <font size="1" style="font-family: Arial;">*&#160;</font> </td> <td width="100%"> <font size="1" style="font-family: Arial;">Except that the expenses reflect the effects of the fund&#8217;s fee waiver/expense reimbursement agreement, including any recoupments, for the first year only.</font> </td> </tr> </table> Principal risks <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">All investments carry a certain amount of risk, and the fund cannot guarantee that it will achieve its investment objective. While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Money market instruments generally have a low risk of loss, but they are not risk-free. The principal risks presented by an investment in the fund are:</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Credit risk:</font></b> <font size="2" style="font-family: Arial;">Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Concentration risk:</font></b> <font size="2" style="font-family: Arial;">The fund will invest a significant portion of its assets in securities issued by companies in the financial services group of industries, including US banking, non-US banking, broker-dealers, insurance companies, finance companies (</font><i><font size="2" style="font-family: Arial;">e.g.</font></i><font size="2" style="font-family: Arial;">, automobile finance) and related asset-backed securities. Accordingly, the fund will be more susceptible to developments that affect those industries than other funds that do not concentrate their investments.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Financial services sector risk:</font></b> <font size="2" style="font-family: Arial;">Investments of the fund in the financial services sector may be particularly affected by economic cycles, business developments, interest rate changes and regulatory changes.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Foreign investing risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments in foreign securities may fall due to adverse political, social and economic developments abroad. However, because the fund&#8217;s foreign investments must be denominated in US dollars, it generally is not subject to the risk of changes in currency valuations.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">US Government securities risk:</font></b> <font size="2" style="font-family: Arial;">There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (&#8220;Fannie Mae&#8221;) or Federal Home Loan Mortgage Corporation (&#8220;Freddie Mac&#8221;), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Market risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the market value of the fund&#8217;s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund&#8217;s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic and political conditions in one country or geographic region could adversely impact market, economic and political conditions in other countries or regions.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Interest rate risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments generally will fall when interest rates rise, and its yield will tend to lag behind prevailing rates.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Liquidity risk:</font></b> <font size="2" style="font-family: Arial;">Although the fund invests in a diversified portfolio of high quality instruments, the fund&#8217;s investments may become less liquid as a result of market developments or adverse investor perception.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results.</font> </p> While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Principal strategies <p align="left"><b><font size="2" style="font-family: Arial;"><br/> Principal investments<br/> </font></b><font size="2" style="font-family: Arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. The fund seeks to achieve its objective by investing in a diversified portfolio of high quality money market instruments of governmental and private issuers. These may include:</font> </p> <br/><ul style="FONT-SIZE: 10pt; MARGIN-LEFT: 16px"> <li> <font size="2" style="font-family: Arial;">short-term obligations of the US government and its agencies and instrumentalities;</font> </li> <li> <font size="2" style="font-family: Arial;">repurchase agreements;</font> </li> <li> <font size="2" style="font-family: Arial;">obligations of issuers in the financial services group of industries; and</font> </li> <li> <font size="2" style="font-family: Arial;">commercial paper, other corporate obligations and asset-backed securities.</font> </li> </ul> <br/><p align="left"> <font size="2" style="font-family: Arial;">Money market instruments generally are short-term debt obligations and similar securities. They also may include longer-term bonds that have variable interest rates or other special features that give them the financial characteristics of short-term debt. The fund invests in foreign money market instruments only if they are denominated in US dollars. The fund will, under normal circumstances, invest more than 25% of its total assets in the financial services group of industries.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management process<br /> </font></b><font size="2" style="font-family: Arial;">UBS Global Asset Management (Americas) Inc. (&#8220;UBS Global AM&#8221;) acts as the investment advisor. As investment advisor, UBS Global AM makes the fund&#8217;s investment decisions. UBS Global AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions. UBS Global AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</font> </p> Fees and expenses of the fund <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">These tables describe the fees and expenses that you may pay if you buy and hold shares of the fund.</font> </p> 0.0000 0.0000 0.0020 0.0025 0.0015 0.0010 0.0005 0.0060 -0.0010 0.0050 ~ http://ubs.com/20130828/role/ScheduleShareholderFees20057 column dei_LegalEntityAxis compact ck0001060517_S000018679Member row primary compact * ~ ~ http://ubs.com/20130828/role/ScheduleAnnualFundOperatingExpenses20058 column dei_LegalEntityAxis compact ck0001060517_S000018679Member row primary compact * ~ Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment) Shareholder fees (fees paid directly from your investment) The fund invests in securities through an underlying master fund, Prime Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Prime Master Fund, including management fees allocated from Prime Master Fund. Management fees are comprised of investment advisory and administration fees. 2014-08-31 Performance <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><b><font size="2" style="font-family: Arial;">Risk/return bar chart and table<br/> </font></b><font size="2" style="font-family: Arial;">The following bar chart and table provide information about the fund&#8217;s performance and thus give some indication of the risks of an investment in the fund.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The bar chart shows how the fund&#8217;s performance has varied from year to year.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The table that follows the bar chart shows the average annual returns over the various time periods for the fund&#8217;s shares.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund&#8217;s past performance does not necessarily indicate how the fund will perform in the future.</font> </p> Total return (2009 was the fund's first full calendar year of operations) UBS Select Prime Investor Fund Annual Returns 0.0026 0.0001 0.0001 0.0001 ~ http://ubs.com/20130828/role/ScheduleAnnualTotalReturnsBarChart20060 column dei_LegalEntityAxis compact ck0001060517_S000018679Member column rr_ProspectusShareClassAxis compact ck0001060517_C000051802Member row primary compact * ~ Best quarter 0.0019 2009-03-31 Worst quarter 0.0000 2011-03-31 Total return January 1 to June 30, 2013: 0.0000 2013-06-30 <p align="left"> <font size="2" style="font-family: Arial;">Total return January 1 to June 30, 2013: 0.00% (Actual total return was 0.0050%)<br /> Best quarter during years shown - 1Q 2009: 0.19%<br /> </font> <font size="2" style="font-family: Arial;">Worst quarters during years shown - 1Q, 2Q &amp; 3Q 2010; 1Q 2011: 0.00%</font><b><font size="2" style="font-family: Arial;"></font></b><font size="2" style="font-family: Arial;">(Actual total returns were 0.0024%)</font> </p> <p align="left"> <font size="2" style="font-family: Arial;">Updated performance information is available by contacting your Financial Advisor or by calling 1-888-793 8637 (Option #1).</font> </p> 0.0001 0.0026 2008-08-01 ~ http://ubs.com/20130828/role/ScheduleAverageAnnualReturnsTransposed20061 column dei_LegalEntityAxis compact ck0001060517_S000018679Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ The fund's past performance does not necessarily indicate how the fund will perform in the future. The following bar chart and table provide information about the fund's performance and thus give some indication of the risks of an investment in the fund. Average annual total returns (for the periods ended December 31, 2012) 1-888-793 8637 (Option #1) Investment objective <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">Maximum current income consistent with liquidity and the preservation of capital.</font> </p> UBS Select Treasury Investor Fund STRXX Example <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund&#8217;s operating expenses remain the same.*</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</font> </p> 51 182 325 740 ~ http://ubs.com/20130828/role/ScheduleExpenseExampleTransposed20066 column dei_LegalEntityAxis compact ck0001060517_S000018680Member row primary compact * ~ <table cellspacing="0" cellpadding="0" border="0"> <tr> <td valign="top" nowrap="nowrap"> <font size="1" style="font-family: Arial;">*&#160;</font> </td> <td width="100%"> <font size="1" style="font-family: Arial;">Except that the expenses reflect the effects of the fund&#8217;s fee waiver/expense reimbursement agreement, including any recoupments, for the first year only.</font> </td> </tr> </table> Principal risks <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">All investments carry a certain amount of risk, and the fund cannot guarantee that it will achieve its investment objective. While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Money market instruments generally have a low risk of loss, but they are not risk-free. The principal risks presented by an investment in the fund are:</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Credit risk:</font></b> <font size="2" style="font-family: Arial;">Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">US Government securities risk:</font></b> <font size="2" style="font-family: Arial;">There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (&#8220;Fannie Mae&#8221;) or Federal Home Loan Mortgage Corporation (&#8220;Freddie Mac&#8221;), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Market risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the market value of the fund&#8217;s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund&#8217;s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic and political conditions in one country or geographic region could adversely impact market, economic and political conditions in other countries or regions.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Interest rate risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments generally will fall when interest rates rise, and its yield will tend to lag behind prevailing rates.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Liquidity risk:</font></b> <font size="2" style="font-family: Arial;">Although the fund invests in securities issued by the US Treasury and in related repurchase agreements, the fund&#8217;s investments may become less liquid as a result of market developments or adverse investor perception.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results.</font> </p> While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Principal strategies <p align="left"><b><font size="2" style="font-family: Arial;"><br/> Principal investments<br/> </font></b><font size="2" style="font-family: Arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. Under normal circumstances, the fund seeks to achieve its objective by investing at least 80% of its net assets (plus the amount of any borrowing for investment purposes) in securities issued by the US Treasury and in related repurchase agreements. However, under normal circumstances the fund expects to invest substantially all of its assets in securities issued by the US Treasury and in related repurchase agreements. The fund may invest a significant percentage of its assets in repurchase agreements. Repurchase agreements involve transactions in which the fund purchases securities issued by the US Treasury and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of interest. While income earned by the fund&#8217;s direct investments in securities issued by the US Treasury may qualify for favorable state and local income taxation, income related to repurchase agreements may not be so advantaged. Investing in repurchase agreements may permit the fund quickly to take advantage of increases in short-term rates.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Money market instruments generally are short-term debt obligations and similar securities. They also may include longer-term bonds that have variable interest rates or other special features that give them the financial characteristics of short-term debt.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management process<br /> </font></b><font size="2" style="font-family: Arial;">UBS Global Asset Management (Americas) Inc. (&#8220;UBS Global AM&#8221;) acts as the investment advisor. As investment advisor, UBS Global AM makes the fund&#8217;s investment decisions. UBS Global AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">UBS Global AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</font> </p> Fees and expenses of the fund <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">These tables describe the fees and expenses that you may pay if you buy and hold shares of the fund.</font> </p> 0.0000 0.0000 0.0020 0.0025 0.0015 0.0010 0.0005 0.0060 -0.0010 0.0050 ~ http://ubs.com/20130828/role/ScheduleShareholderFees20064 column dei_LegalEntityAxis compact ck0001060517_S000018680Member row primary compact * ~ ~ http://ubs.com/20130828/role/ScheduleAnnualFundOperatingExpenses20065 column dei_LegalEntityAxis compact ck0001060517_S000018680Member row primary compact * ~ Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment) Shareholder fees (fees paid directly from your investment) The fund invests in securities through an underlying master fund, Treasury Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Treasury Master Fund, including management fees allocated from Treasury Master Fund. Management fees are comprised of investment advisory and administration fees. 2014-08-31 Performance <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><b><font size="2" style="font-family: Arial;">Risk/return bar chart and table<br/> </font></b><font size="2" style="font-family: Arial;">The following bar chart and table provide information about the fund&#8217;s performance and thus give some indication of the risks of an investment in the fund.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The bar chart shows how the fund&#8217;s performance has varied from year to year.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The table that follows the bar chart shows the average annual returns over the various time periods for the fund&#8217;s shares.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund&#8217;s past performance does not necessarily indicate how the fund will perform in the future.</font> </p> Total return (2009 was the fund's first full calendar year of operations) UBS Select Treasury Investor Fund Annual Total Returns 0.0001 0.0001 0.0001 0.0001 ~ http://ubs.com/20130828/role/ScheduleAnnualTotalReturnsBarChart20067 column dei_LegalEntityAxis compact ck0001060517_S000018680Member column rr_ProspectusShareClassAxis compact ck0001060517_C000051803Member row primary compact * ~ Best quarter 0.0000 2009-12-31 Worst quarter 0.0000 2011-03-31 Total return January 1 to June 30, 2013: 0.0000 2013-06-30 <p align="left"> <font size="2" style="font-family: Arial;">Total return January 1 to June 30, 2013: 0.00% (Actual total return was 0.0050%)<br /> Best quarter during years shown - 4Q 2009: 0.00%</font><b><font size="2" style="font-family: Arial;"></font></b><font size="2" style="font-family: Arial;">(Actual total return was 0.0037%)<br /> </font><font size="2" style="font-family: Arial;">Worst quarters during years shown - 2Q &amp; 3Q 2009; 1Q, 2Q &amp; 3Q 2010; 1Q 2011: 0.00%</font><b><font size="2" style="font-family: Arial;"></font></b><font size="2" style="font-family: Arial;">(Actual total returns were 0.0024%)</font> </p> <p align="left"> <font size="2" style="font-family: Arial;">Updated performance information is available by contacting your Financial Advisor or by calling 1-888-793 8637 (Option #1).</font> </p> 0.0001 0.0002 2008-09-18 ~ http://ubs.com/20130828/role/ScheduleAverageAnnualReturnsTransposed20068 column dei_LegalEntityAxis compact ck0001060517_S000018680Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ The fund's past performance does not necessarily indicate how the fund will perform in the future. The following bar chart and table provide information about the fund's performance and thus give some indication of the risks of an investment in the fund. Average annual total returns (for the periods ended December 31, 2012) 1-888-793 8637 (Option #1) Investment objective <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">Maximum current income consistent with liquidity and the preservation of capital.</font> </p> UBS Select Tax-Free Investor Fund SFRXX Example <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund&#8217;s operating expenses remain the same.*</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</font> </p> 51 243 450 1049 ~ http://ubs.com/20130828/role/ScheduleExpenseExampleTransposed20073 column dei_LegalEntityAxis compact ck0001060517_S000018681Member row primary compact * ~ <table cellspacing="0" cellpadding="0" border="0"> <tr> <td valign="top" nowrap="nowrap"> <font size="1" style="font-family: Arial;">*&#160;</font> </td> <td width="100%"> <font size="1" style="font-family: Arial;">Except that the expenses reflect the effects of the fund&#8217;s fee waiver/expense reimbursement agreement, including any recoupments, for the first year only.</font> </td> </tr> </table> Principal risks <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">All investments carry a certain amount of risk, and the fund cannot guarantee that it will achieve its investment objective. While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Money market instruments generally have a low risk of loss, but they are not risk-free. The principal risks presented by an investment in the fund are:</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Credit risk:</font></b> <font size="2" style="font-family: Arial;">Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Interest rate risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments generally will fall when interest rates rise, and its yield will tend to lag behind prevailing rates.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Market risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the market value of the fund&#8217;s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund&#8217;s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic and political conditions in one country or geographic region could adversely impact market, economic and political conditions in other countries or regions.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Liquidity risk:</font></b> <font size="2" style="font-family: Arial;">Although the fund invests in a diversified portfolio of high quality instruments, the fund&#8217;s investments may become less liquid as a result of market developments or adverse investor perception.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Municipal securities risk:</font></b> <font size="2" style="font-family: Arial;">Municipal securities are subject to interest rate and credit risks. The ability of a municipal issuer to make payments and the value of municipal securities can be affected by uncertainties in the municipal securities market. Such uncertainties could cause increased volatility in the municipal securities market and could negatively impact the fund&#8217;s net asset value and/or the distributions paid by the fund. Municipalities continue to experience difficulties in the current economic and political environment.</font> </p> While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Principal strategies <p align="left"><b><font size="2" style="font-family: Arial;"><br/> Principal investments<br/> </font></b><font size="2" style="font-family: Arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. The fund seeks to achieve its objective by investing in a diversified portfolio of high quality, municipal money market instruments.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Under normal circumstances, the fund will invest at least 80% of its net assets (plus the amount of any borrowing for investment purposes) in investments, the income from which is exempt from federal income tax. Investments that are subject to the alternative minimum tax are not counted towards satisfying the 80% test in the foregoing sentence. Under normal circumstances, the fund may invest only up to 20% of its net assets in municipal securities that pay interest that is an item of tax preference for purposes of the alternative minimum tax.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Money market instruments generally are short-term debt obligations and similar securities. They also may include longer-term bonds that have variable interest rates or other special features that give them the financial characteristics of short-term debt.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management process<br /> </font></b><font size="2" style="font-family: Arial;">UBS Global Asset Management (Americas) Inc. (&#8220;UBS Global AM&#8221;) acts as the investment advisor. As investment advisor, UBS Global AM makes the fund&#8217;s investment decisions. UBS Global AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</font> </p> Fees and expenses of the fund <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">These tables describe the fees and expenses that you may pay if you buy and hold shares of the fund.</font> </p> 0.0000 0.0000 0.0020 0.0025 0.0043 0.0010 0.0033 0.0088 -0.0038 0.0050 ~ http://ubs.com/20130828/role/ScheduleShareholderFees20071 column dei_LegalEntityAxis compact ck0001060517_S000018681Member row primary compact * ~ ~ http://ubs.com/20130828/role/ScheduleAnnualFundOperatingExpenses20072 column dei_LegalEntityAxis compact ck0001060517_S000018681Member row primary compact * ~ Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment) Shareholder fees (fees paid directly from your investment) The fund invests in securities through an underlying master fund, Tax-Free Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Tax-Free Master Fund, including management fees allocated from Tax-Free Master Fund. Management fees are comprised of investment advisory and administration fees. 2014-08-31 Performance <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><b><font size="2" style="font-family: Arial;">Risk/return bar chart and table<br/> </font></b><font size="2" style="font-family: Arial;">The following bar chart and table provide information about the fund&#8217;s performance and thus give some indication of the risks of an investment in the fund.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The bar chart shows how the fund&#8217;s performance has varied from year to year.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The table that follows the bar chart shows the average annual returns over the various time periods for the fund&#8217;s shares.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund&#8217;s past performance does not necessarily indicate how the fund will perform in the future.</font> </p> Total return (2009 was the fund's first full calendar year of operations) UBS Select Tax-Free Investor Fund Annual Total Returns 0.0005 0.0002 0.0001 0.0001 ~ http://ubs.com/20130828/role/ScheduleAnnualTotalReturnsBarChart20074 column dei_LegalEntityAxis compact ck0001060517_S000018681Member column rr_ProspectusShareClassAxis compact ck0001060517_C000051804Member row primary compact * ~ Best quarter 0.0003 2009-03-31 Worst quarter 0.0000 2011-03-31 Total return January 1 to June 30, 2013: 0.0000 2013-06-30 <p align="left"> <font size="2" style="font-family: Arial;">Total return January 1 to June 30, 2013: 0.00% (Actual total return was 0.0050%)<br /> Best quarter during years shown - 1Q 2009: 0.03%<br /> </font> <font size="2" style="font-family: Arial;">Worst quarters during years shown - 3Q 2009; 1Q, 2Q &amp; 3Q 2010; 1Q 2011: 0.00%</font><b><font size="2" style="font-family: Arial;"></font></b><font size="2" style="font-family: Arial;">(Actual total returns were 0.0024%)</font> </p> <p align="left"> <font size="2" style="font-family: Arial;">Updated performance information is available by contacting your Financial Advisor or by calling 1-888-793 8637 (Option #1).</font> </p> 0.0001 0.0012 2008-09-22 ~ http://ubs.com/20130828/role/ScheduleAverageAnnualReturnsTransposed20075 column dei_LegalEntityAxis compact ck0001060517_S000018681Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ The fund's past performance does not necessarily indicate how the fund will perform in the future. The following bar chart and table provide information about the fund's performance and thus give some indication of the risks of an investment in the fund. Average annual total returns (for the periods ended December 31, 2012) 1-888-793 8637 (Option #1) Investment objective <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">Maximum current income exempt from federal income tax consistent with liquidity and the preservation of capital.</font> </p> UBS Select Prime Capital Fund SPCXX Example <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund&#8217;s operating expenses remain the same.*</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</font> </p> 20 99 186 440 ~ http://ubs.com/20130828/role/ScheduleExpenseExampleTransposed20080 column dei_LegalEntityAxis compact ck0001060517_S000023599Member row primary compact * ~ <table cellspacing="0" cellpadding="0" border="0"> <tr> <td valign="top" nowrap="nowrap"> <font size="1" style="font-family: Arial;">*&#160;&#160;&#160;&#160;&#160;</font> </td> <td width="100%"> <font size="1" style="font-family: Arial;">Except that the expenses reflect the effects of the fund&#8217;s fee waiver/expense reimbursement agreement, including any recoupments, for the first year only.</font> </td> </tr> </table> Fees and expenses of the fund <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">These tables describe the fees and expenses that you may pay if you buy and hold shares of the fund.</font> </p> 0.0000 0.0000 0.0020 0.0000 0.0016 0.0015 0.0001 0.0036 -0.0016 0.0020 ~ http://ubs.com/20130828/role/ScheduleShareholderFees20078 column dei_LegalEntityAxis compact ck0001060517_S000023599Member row primary compact * ~ ~ http://ubs.com/20130828/role/ScheduleAnnualFundOperatingExpenses20079 column dei_LegalEntityAxis compact ck0001060517_S000023599Member row primary compact * ~ Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment) Shareholder fees (fees paid directly from your investment) The fund invests in securities through an underlying master fund, Prime Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Prime Master Fund, including management fees allocated from Prime Master Fund. Management fees are comprised of investment advisory and administration fees. 2014-08-31 Principal strategies <p align="left"><b><font size="2" style="font-family: Arial;"><br/> Principal investments<br/> </font></b><font size="2" style="font-family: Arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. The fund seeks to achieve its objective by investing in a diversified portfolio of high quality money market instruments of governmental and private issuers. These may include:</font> </p> <br/><ul style="FONT-SIZE: 10pt; MARGIN-LEFT: 16px"> <li> <font size="2" style="font-family: Arial;">short-term obligations of the US government and its agencies and instrumentalities;</font><br /> &#160; </li> <li> <font size="2" style="font-family: Arial;">repurchase agreements;</font><br /> &#160; </li> <li> <font size="2" style="font-family: Arial;">obligations of issuers in the financial services group of industries; and</font><br /> &#160; </li> <li> <font size="2" style="font-family: Arial;">commercial paper, other corporate obligations and asset-backed securities.</font> </li> </ul> <br/><p align="left"> <font size="2" style="font-family: Arial;">Money market instruments generally are short-term debt obligations and similar securities. They also may include longer-term bonds that have variable interest rates or other special features that give them the financial characteristics of short-term debt. The fund invests in foreign money market instruments only if they are denominated in US dollars. The fund will, under normal circumstances, invest more than 25% of its total assets in the financial services group of industries.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management process<br /> </font></b><font size="2" style="font-family: Arial;">UBS Global Asset Management (Americas) Inc. (&#8220;UBS Global AM&#8221;) acts as the investment advisor. As investment advisor, UBS Global AM makes the fund&#8217;s investment decisions. UBS Global AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions. UBS Global AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</font> </p> Principal risks <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">All investments carry a certain amount of risk, and the fund cannot guarantee that it will achieve its investment objective. While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Money market instruments generally have a low risk of loss, but they are not risk-free. The principal risks presented by an investment in the fund are:</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Credit risk:</font></b> <font size="2" style="font-family: Arial;">Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Concentration risk:</font></b> <font size="2" style="font-family: Arial;">The fund will invest a significant portion of its assets in securities issued by companies in the financial services group of industries, including US banking, non-US banking, broker-dealers, insurance companies, finance companies (</font><i><font size="2" style="font-family: Arial;">e.g.</font></i><font size="2" style="font-family: Arial;">, automobile finance) and related asset-backed securities. Accordingly, the fund will be more susceptible to developments that affect those industries than other funds that do not concentrate their investments.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Financial services sector risk:</font></b> <font size="2" style="font-family: Arial;">Investments of the fund in the financial services sector may be particularly affected by economic cycles, business developments, interest rate changes and regulatory changes.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Foreign investing risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments in foreign securities may fall due to adverse political, social and economic developments abroad. However, because the fund&#8217;s foreign investments must be denominated in US dollars, it generally is not subject to the risk of changes in currency valuations.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">US Government securities risk:</font></b> <font size="2" style="font-family: Arial;">There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (&#8220;Fannie Mae&#8221;) or Federal Home Loan Mortgage Corporation (&#8220;Freddie Mac&#8221;), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Market risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the market value of the fund&#8217;s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund&#8217;s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic and political conditions in one country or geographic region could adversely impact market, economic and political conditions in other countries or regions.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Interest rate risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments generally will fall when interest rates rise, and its yield will tend to lag behind prevailing rates.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Liquidity risk:</font></b> <font size="2" style="font-family: Arial;">Although the fund invests in a diversified portfolio of high quality instruments, the fund&#8217;s investments may become less liquid as a result of market developments or adverse investor perception.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results.</font> </p> While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Investment objective <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">Maximum current income consistent with liquidity and the preservation of capital.</font> </p> Performance <p align="left"><br/> <font size="2" style="font-family: Arial;">There is no performance information quoted for the fund as the fund had not operated for a full calendar year as of the date of this prospectus.</font> </p> There is no performance information quoted for the fund as the fund had not operated for a full calendar year as of the date of this prospectus. UBS Select Treasury Capital Fund STCXX Example <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund&#8217;s operating expenses remain the same.*</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</font> </p> 20 102 191 451 ~ http://ubs.com/20130828/role/ScheduleExpenseExampleTransposed20085 column dei_LegalEntityAxis compact ck0001060517_S000023600Member row primary compact * ~ <table cellspacing="0" cellpadding="0" border="0"> <tr> <td valign="top" nowrap="nowrap"> <font size="1" style="font-family: Arial;">*&#160;&#160;&#160;&#160;&#160;</font> </td> <td width="100%"> <font size="1" style="font-family: Arial;">Except that the expenses reflect the effects of the fund&#8217;s fee waiver/expense reimbursement agreement, including any recoupments, for the first year only.</font> </td> </tr> </table> Fees and expenses of the fund <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">These tables describe the fees and expenses that you may pay if you buy and hold shares of the fund.</font> </p> 0.0000 0.0000 0.0020 0.0000 0.0017 0.0015 0.0002 0.0037 -0.0017 0.0020 ~ http://ubs.com/20130828/role/ScheduleShareholderFees20083 column dei_LegalEntityAxis compact ck0001060517_S000023600Member row primary compact * ~ ~ http://ubs.com/20130828/role/ScheduleAnnualFundOperatingExpenses20084 column dei_LegalEntityAxis compact ck0001060517_S000023600Member row primary compact * ~ Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment) Shareholder fees (fees paid directly from your investment) The fund invests in securities through an underlying master fund, Treasury Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Treasury Master Fund, including management fees allocated from Treasury Master Fund. Management fees are comprised of investment advisory and administration fees. 2014-08-31 Principal strategies <p align="left"><b><font size="2" style="font-family: Arial;"><br/> Principal investments<br/> </font></b><font size="2" style="font-family: Arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. Under normal circumstances, the fund seeks to achieve its objective by investing at least 80% of its net assets (plus the amount of any borrowing for investment purposes) in securities issued by the US Treasury and in related repurchase agreements. However, under normal circumstances the fund expects to invest substantially all of its assets in securities issued by the US Treasury and in related repurchase agreements. The fund may invest a significant percentage of its assets in repurchase agreements. Repurchase agreements involve transactions in which the fund purchases securities issued by the US Treasury and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of interest. While income earned by the fund&#8217;s direct investments in securities issued by the US Treasury may qualify for favorable state and local income taxation, income related to repurchase agreements may not be so advantaged. Investing in repurchase agreements may permit the fund quickly to take advantage of increases in short-term rates.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Money market instruments generally are short-term debt obligations and similar securities. They also may include longer-term bonds that have variable interest rates or other special features that give them the financial characteristics of short-term debt.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management process<br /> </font></b><font size="2" style="font-family: Arial;">UBS Global Asset Management (Americas) Inc. (&#8220;UBS Global AM&#8221;) acts as the investment advisor. As investment advisor, UBS Global AM makes the fund&#8217;s investment decisions. UBS Global AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">UBS Global AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</font> </p> Principal risks <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">All investments carry a certain amount of risk, and the fund cannot guarantee that it will achieve its investment objective. While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Money market instruments generally have a low risk of loss, but they are not risk-free. The principal risks presented by an investment in the fund are:</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Credit risk:</font></b> <font size="2" style="font-family: Arial;">Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">US Government securities risk:</font></b> <font size="2" style="font-family: Arial;">There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (&#8220;Fannie Mae&#8221;) or Federal Home Loan Mortgage Corporation (&#8220;Freddie Mac&#8221;), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Market risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the market value of the fund&#8217;s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund&#8217;s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic and political conditions in one country or geographic region could adversely impact market, economic and political conditions in other countries or regions.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Interest rate risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments generally will fall when interest rates rise, and its yield will tend to lag behind prevailing rates.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Liquidity risk:</font></b> <font size="2" style="font-family: Arial;">Although the fund invests in securities issued by the US Treasury and in related repurchase agreements, the fund&#8217;s investments may become less liquid as a result of market developments or adverse investor perception.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results.</font> </p> While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Investment objective <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">Maximum current income consistent with liquidity and the preservation of capital.</font> </p> Performance <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">There is no performance information quoted for the fund as the fund had not operated for a full calendar year as of the date of this prospectus.</font> </p> There is no performance information quoted for the fund as the fund had not operated for a full calendar year as of the date of this prospectus. UBS Select Tax-Free Capital Fund STEXX Example <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund&#8217;s operating expenses remain the same.*</font> </p> 20 102 191 451 ~ http://ubs.com/20130828/role/ScheduleExpenseExampleTransposed20090 column dei_LegalEntityAxis compact ck0001060517_S000023601Member row primary compact * ~ <table cellspacing="0" cellpadding="0" border="0"> <tr> <td valign="top" nowrap="nowrap"> <font size="1" style="font-family: Arial;">*&#160;&#160;&#160;&#160;&#160;</font> </td> <td width="100%"> <font size="1" style="font-family: Arial;">Except that the expenses reflect the effects of the fund&#8217;s fee waiver/expense reimbursement agreement, including any recoupments, for the first year only.</font> </td> </tr> </table> Although your actual costs may be higher or lower, based on these assumptions your costs would be: Fees and expenses of the fund <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">These tables describe the fees and expenses that you may pay if you buy and hold shares of the fund.</font> </p> 0.0000 0.0000 0.0020 0.0000 0.0017 0.0015 0.0002 0.0037 -0.0017 0.0020 ~ http://ubs.com/20130828/role/ScheduleShareholderFees20088 column dei_LegalEntityAxis compact ck0001060517_S000023601Member row primary compact * ~ ~ http://ubs.com/20130828/role/ScheduleAnnualFundOperatingExpenses20089 column dei_LegalEntityAxis compact ck0001060517_S000023601Member row primary compact * ~ Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment) Shareholder fees (fees paid directly from your investment) The fund invests in securities through an underlying master fund, Tax-Free Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Tax-Free Master Fund, including management fees allocated from Tax-Free Master Fund. Management fees are comprised of investment advisory and administration fees. 2014-08-31 Principal strategies <p align="left"><b><font size="2" style="font-family: Arial;"><br/> Principal investments<br/> </font></b><font size="2" style="font-family: Arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. The fund seeks to achieve its objective by investing in a diversified portfolio of high quality, municipal money market instruments.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Under normal circumstances, the fund will invest at least 80% of its net assets (plus the amount of any borrowing for investment purposes) in investments, the income from which is exempt from federal income tax. Investments that are subject to the alternative minimum tax are not counted towards satisfying the 80% test in the foregoing sentence. Under normal circumstances, the fund may invest only up to 20% of its net assets in municipal securities that pay interest that is an item of tax preference for purposes of the alternative minimum tax.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">Money market instruments generally are short-term debt obligations and similar securities. They also may include longer-term bonds that have variable interest rates or other special features that give them the financial characteristics of short-term debt.</font> </p> <br/><p align="left"> <font size="2" style="font-family: Arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management process<br /> </font></b><font size="2" style="font-family: Arial;">UBS Global Asset Management (Americas) Inc. (&#8220;UBS Global AM&#8221;) acts as the investment advisor. As investment advisor, UBS Global AM makes the fund&#8217;s investment decisions. UBS Global AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</font> </p> Principal risks <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">All investments carry a certain amount of risk, and the fund cannot guarantee that it will achieve its investment objective. While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Money market instruments generally have a low risk of loss, but they are not risk-free. The principal risks presented by an investment in the fund are:</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Credit risk:</font></b> <font size="2" style="font-family: Arial;">Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Interest rate risk:</font></b> <font size="2" style="font-family: Arial;">The value of the fund&#8217;s investments generally will fall when interest rates rise, and its yield will tend to lag behind prevailing rates.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Market risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the market value of the fund&#8217;s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund&#8217;s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic and political conditions in one country or geographic region could adversely impact market, economic and political conditions in other countries or regions.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Liquidity risk:</font></b> <font size="2" style="font-family: Arial;">Although the fund invests in a diversified portfolio of high quality instruments, the fund&#8217;s investments may become less liquid as a result of market developments or adverse investor perception.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Management risk:</font></b> <font size="2" style="font-family: Arial;">The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results.</font> </p> <br/><p align="left"> <b><font size="2" style="font-family: Arial;">Municipal securities risk:</font></b> <font size="2" style="font-family: Arial;">Municipal securities are subject to interest rate and credit risks. The ability of a municipal issuer to make payments and the value of municipal securities can be affected by uncertainties in the municipal securities market. Such uncertainties could cause increased volatility in the municipal securities market and could negatively impact the fund&#8217;s net asset value and/or the distributions paid by the fund. Municipalities continue to experience difficulties in the current economic and political environment.</font> </p> While the fund seeks to maintain the value of your investment at $1.00 per share, you may lose money by investing in the fund. An investment in the fund is not a bank deposit and is neither insured nor guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Investment objective <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">Maximum current income exempt from federal income tax consistent with liquidity and the preservation of capital.</font> </p> Performance <p align="left"><b><font size="2" style="font-family: Arial;"><br/> </font></b><font size="2" style="font-family: Arial;">There is no performance information quoted for the fund as the fund had not operated for a full calendar year as of the date of this prospectus.</font> </p> There is no performance information quoted for the fund as the fund had not operated for a full calendar year as of the date of this prospectus. 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