485BPOS
2012-06-30
0001165382
2012-10-31
ACTIVE ASSETS INSTITUTIONAL GOVERNMENT SECURITIES TRUST
false
2012-10-26
2012-10-31
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<tt>The Fund is a money market fund that seeks high current income, preservation of<br />capital and liquidity.</tt>
<tt>The example below is intended to help you compare the cost of investing in the<br />Fund with the cost of investing in other mutual funds.<br /> <br />The example assumes that you invest $10,000 in the Fund, your investment has a<br />5% return each year, and the Fund's operating expenses remain the same. Although<br />your actual costs may be higher or lower, based on these assumptions your costs<br />would be:</tt>
<tt>The Fund invests in high quality, short-term debt obligations. In selecting<br />investments, the Adviser and/or Morgan Stanley Investment Management Limited<br />("Sub-Adviser") seek to maintain the Fund's share price at $1.00. The Fund's<br />investments include the following money market instruments: corporate<br />obligations (including but not limited to commercial paper); debt obligations <br />of U.S.-regulated banks (including domestic branches or subsidiaries of foreign<br />banks) and instruments secured by those obligations (including certificates of<br />deposit); certificates of deposit of savings banks and savings and loan<br />associations; debt obligations issued or guaranteed as to principal and interest<br />by the U.S. Government, its agencies and instrumentalities, including U.S.<br />government securities guaranteed under the Federal Deposit Insurance Corporation<br />("FDIC") Temporary Liquidity Guarantee Program; repurchase agreements; U.S.<br />dollar-denominated foreign bank obligations; asset-backed securities; and<br />tax-exempt variable rate demand notes.</tt>
Active Assets Institutional Money Trust
Example
Investment Objectives
The Fund's past performance does not indicate how the Fund will perform in the future.
Principal Risks
Annual Total Returns--Calendar Years
Past Performance
<tt>For the Fund's most recent 7-day annualized yield you may call toll-free (800)<br />869-NEWS.</tt>
The bar chart and table below provide some indication of the risks of investing
in the Fund by showing changes in the Fund's performance from year to year and
by showing the Fund's average annual returns for the one, five and 10 year periods.
<tt>The year-to-date total return as of September 30, 2012 was 0.10%.<br /> <br />High Quarter 12/31/06 1.33%<br />Low Quarter 9/30/11 0.00%</tt>
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Average Annual Total Returns (as of December 31, 2011)
Although the Fund seeks to preserve the value of your investment at $1.00 per
share, if it is unable to do so, it is possible to lose money by investing in
the Fund.
<tt>There is no assurance that the Fund will achieve its investment objectives.<br />Although the Fund seeks to preserve the value of your investment at $1.00 per<br />share, if it is unable to do so, it is possible to lose money by investing in <br />the Fund. The principal risks of investing in the Fund include:<br /> <br />• Credit and Interest Rate Risk. Debt obligations, such as bonds, are subject to<br />  two types of risk: credit risk and interest rate risk. Credit risk refers to <br />  the possibility that the issuer of a security will be unable to make interest<br />  payments and/or repay the principal on its debt. Interest rate risk refers to<br />  fluctuations in the value of a debt security resulting from changes in the<br />  general level of interest rates.<br /> <br />• U.S. Government Securities. With respect to U.S. government securities that<br />  are not backed by the full faith and credit of the United States, there is the<br />  risk that the U.S. Government will not provide financial support to such U.S.<br />  government agencies, instrumentalities or sponsored enterprises if it is not<br />  obligated to do so by law.<br /> <br />• Asset-Backed Securities Risk. Asset-backed securities involve the risk that<br />  various federal and state consumer laws and other legal and economic factors may<br />  result in the collateral backing the securities being insufficient to support<br />  payment on the securities. Some asset-backed securities also entail prepayment<br />  risk, which may vary depending on the type of asset.<br /> <br />• Tax-Exempt Variable Rate Demand Notes Risk. Due to cyclical supply and demand<br />  considerations, at times the yields on these obligations can exceed the yield <br />  on taxable money market obligations.<br /> <br />• Foreign Money Market Securities. Investing in money market securities of<br />  foreign issuers involves some additional risks, including the possibility of<br />  adverse political, economic or other developments affecting the issuers of these<br />  securities.<br /> <br />• Repurchase Agreements. Repurchase agreements are subject to risks associated<br />  with the possibility of default by the seller at a time when the collateral <br />  has declined in value, or insolvency of the seller, which may affect the Fund's<br />  right to control the collateral and result in certain costs and delays.<br /> <br />Shares of the Fund are not bank deposits and are not guaranteed or insured by<br />the FDIC or any other government agency.</tt>
Fees and Expenses
Principal Investment Strategies
<tt>The bar chart and table below provide some indication of the risks of investing<br />in the Fund by showing changes in the Fund's performance from year to year and<br />by showing the Fund's average annual returns for the one, five and 10 year periods. <br />The Fund's past performance does not indicate how the Fund will perform in the future.</tt>
<tt>The table below describes the fees and expenses that you may pay if you buy and<br />hold shares of the Fund. The Fund is a no-load fund. The Fund does not impose<br />any sales charges or distribution and service (12b-1) fees.</tt>
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Shares of the Fund are not bank deposits and are not guaranteed or insured by the FDIC or any other government agency.
(800) 869-News
AVIXX
0.0167
Low Quarter
High Quarter
2012-09-30
16
2006-12-31
52
0.0000
0.0125
-0.0001
0.0012
205
90
0.0524
0.0133
0.0006
0.0007
0.0273
0.0010
These fee waivers and/or expense reimbursements will continue for at least one
year or until such time that the Fund's Board of Trustees acts to discontinue
all or a portion of such waivers and/or reimbursements when it deems such action
is appropriate.
2011-09-30
0.0019
0.0165
0.0316
The year-to-date total return
0.0006
0.0103
0.00
0.0203
0.0016
0.0017
0.0501
0.0010
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<tt>The Fund is a money market fund that seeks to provide high current income,<br />preservation of capital and liquidity.</tt>
<tt>The example below is intended to help you compare the cost of investing in the<br />Fund with the cost of investing in other mutual funds.<br /> <br />The example assumes that you invest $10,000 in the Fund, your investment has a<br />5% return each year, and the Fund's operating expenses remain the same. Although<br />your actual costs may be higher or lower, based on these assumptions your costs<br />would be:</tt>
<tt>The Fund invests at least 80% of its assets in high quality, short-term U.S.<br />government securities. In selecting investments, the Adviser and/or Morgan<br />Stanley Investment Management Limited ("Sub-Adviser") seek to maintain the<br />Fund's share price at $1.00. The U.S. government securities that the Fund <br />may purchase include: U.S. Treasury bills, notes and bonds, all of which are <br />direct obligations of the U.S. Government; securities issued by agencies and<br />instrumentalities of the U.S. Government, which are backed by the full faith and<br />credit of the United States; securities issued by agencies and instrumentalities<br />which are not backed by the full faith and credit of the United States, but<br />whose issuing agency or instrumentality has the right to borrow from the U.S.<br />Treasury to meet its obligations; securities issued by agencies and<br />instrumentalities which are backed solely by the credit of the issuing agency <br />or instrumentality; and securities guaranteed under the FDIC Temporary Liquidity<br />Guarantee Program. The Fund also may invest up to 10% of its assets in FDIC<br />insured certificates of deposit of banks and savings and loan institutions. In<br />addition, the Fund may invest in repurchase agreements.</tt>
Active Assets Institutional Government Securities Trust
Example
Investment Objectives
The Fund's past performance does not indicate how the Fund will perform in the future.
Principal Risks
Annual Total Return--Calendar Years
Past Performance
<tt>For the Fund's most recent 7-day annualized yield you may call toll-free (800)<br />869-NEWS.</tt>
The bar chart and table below provide some indication of the risks of investing
in the Fund by showing changes in the Fund's performance from year to year and
by showing the Fund's average annual returns for the one and five year periods
and since inception.
<tt>The year-to-date total return as of September 30, 2012 was 0.01%.<br /> <br />High Quarter 12/31/06 1.31%<br />Low Quarter 3/31/10 0.00%</tt>
Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Average Annual Total Returns (as of December 31, 2011)
Although the Fund seeks to preserve the value of your investment at $1.00 per share,
if it is unable to do so, it is possible to lose money by investing in the Fund.
<tt>There is no assurance that the Fund will achieve its investment objectives.<br />Although the Fund seeks to preserve the value of your investment at $1.00 per<br />share, if it is unable to do so, it is possible to lose money by investing in<br />the Fund. The principal risks of investing in the Fund include:<br /> <br />• Credit and Interest Rate Risk. Debt obligations, such as bonds, are subject to<br />  two types of risk: credit risk and interest rate risk. Credit risk refers to <br />  the possibility that the issuer of a security will be unable to make interest<br />  payments and/or repay the principal on its debt. Interest rate risk refers to<br />  fluctuations in the value of a debt security resulting from changes in the<br />  general level of interest rates.<br /> <br />• U.S. Government Securities. With respect to U.S. government securities that<br />  are not backed by the full faith and credit of the United States, there is the<br />  risk that the U.S. Government will not provide financial support to such U.S.<br />  government agencies, instrumentalities or sponsored enterprises if it is not<br />  obligated to do so by law.<br /> <br />• Repurchase Agreements. Repurchase agreements are subject to risks associated<br />  with the possibility of default by the seller at a time when the collateral has<br />  declined in value, or insolvency of the seller, which may affect the Fund's<br />  right to control the collateral and result in certain costs and delays.<br /> <br />Shares of the Fund are not bank deposits and are not guaranteed or insured by<br />the FDIC or any other government agency.</tt>
Fees and Expenses
Principal Investment Strategies
<tt>The bar chart and table below provide some indication of the risks of investing<br />in the Fund by showing changes in the Fund's performance from year to year and<br />by showing the Fund's average annual returns for the one and five year periods<br />and since inception. The Fund's past performance does not indicate how the Fund<br />will perform in the future.</tt>
<tt>The table below describes the fees and expenses that you may pay if you buy and<br />hold shares of the Fund. The Fund is a no-load fund. The Fund does not impose<br />any sales charges or distribution and service (12b-1) fees.</tt>
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Shares of the Fund are not bank deposits and are not guaranteed or insured by the FDIC or any other government agency.
(800) 869-NEWS
AISXX
Low Quarter
High Quarter
2012-09-30
11
2006-12-31
35
0.0000
0.0130
-0.0006
0.0004
141
62
0.0510
0.0131
0.0001
0.0007
0.0234
0.0010
These fee waivers and/or expense reimbursements will continue for at least
one year or until such time as the Fund's Board of Trustees acts to discontinue
all or a portion of such waivers and/or reimbursements when it deems such action
appropriate.
2010-03-31
0.0011
0.0150
0.0314
The year-to-date total return
0.0001
0.0109
0.00
0.0011
0.0017
0.0494
0.0198
2002-11-04
0.0001
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2012-10-31
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2012-10-31
2012-10-31
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iso4217:USD
The Fund's "Adviser," Morgan Stanley Investment Management Inc., and the Fund's "Administrator," Morgan Stanley Services Company Inc., have contractually agreed to assume all operating expenses of the Fund (except for brokerage fees) and to waive the advisory fee and administration fee, as applicable, to the extent that such expenses and fees on an annualized basis exceed 0.20% of the average daily net assets of the Fund. This arrangement had no effect during the most recent fiscal year. In addition, the Fund's Adviser and Administrator have agreed to waive and/or reimburse all or a portion of the Fund's advisory fee and administration fee, respectively, to the extent that total expenses exceed total income of the Fund on a daily basis. These fee waivers and/or expense reimbursements will continue for at least one year or until such time that the Fund's Board of Trustees acts to discontinue all or a portion of such waivers and/or reimbursements when it deems such action is appropriate.
The Fund's "Adviser," Morgan Stanley Investment Management Inc., and the Fund's "Administrator," Morgan Stanley Services Company Inc., have contractually agreed to assume all operating expenses of the Fund (except for brokerage fees) and to waive the advisory fee and administration fee, as applicable, to the extent that such expenses and fees on an annualized basis exceed 0.20% of the average daily net assets of the Fund. This arrangement had no effect during the most recent fiscal year. In addition, the Fund's Adviser and its Administrator have agreed to waive and/or reimburse all or a portion of the Fund's advisory fee and administration fee, respectively, to the extent that total expenses exceed total income on a daily basis. These fee waivers and/or expense reimbursements will continue for at least one year or until such time as the Fund's Board of Trustees acts to discontinue all or a portion of such waivers and/or reimbursements when it deems such action appropriate.