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2013-09-30 0000798365 ck0000798365:S000035292Member ck0000798365:S000035292Member rr:AfterTaxesOnDistributionsAndSalesMember ck0000798365:C000108547Member 2013-09-30 2013-09-30 0000798365 ck0000798365:S000035292Member ck0000798365:S000035292Member ck0000798365:index_MSCI_ACWISM_reflects_no_deductions_for_fees_expenses_or_taxesMember 2013-09-30 2013-09-30 xbrli:pure iso4217:USD The inception date for the Institutional Class shares is December 30, 2011. Performance information for the Institutional Class prior to that date reflects the actual performance of the Fund's Investor Class (and uses the actual expenses of the Investor Class, for such period of time), without any adjustments. The Adviser is contractually obligated to waive fees or reimburse expenses in order to limit Ariel Focus Fund's total annual operating expenses to 1.25% of net assets for the Investor Class and 1.00% of net assets for Class I through the end of the fiscal year ending September 30, 2014. No termination of this agreement by either the Board of Trustees or the Adviser may be effective until, at the earliest, October 1, 2014. The inception date for the Institutional Class shares is December 30, 2011. Performance information for the Institutional Class prior to that date reflects the actual performance of the Fund's Investor Class (and uses the actual expenses of the Investor Class, for such period of time), without any adjustments. The Adviser is contractually obligated to waive fees or reimburse expenses in order to limit Ariel Discovery Fund's total annual operating expenses to 1.50% of net assets for the Investor Class and 1.25% of net assets for Class I through the end of the fiscal year ending September 30, 2014. No termination of this agreement by either the Board of Trustees or the Adviser may be effective until, at the earliest, October 1, 2014. The Adviser is contractually obligated to waive fees or reimburse expenses in order to limit Ariel International Equity Fund's total annual operating expenses to 1.40% of net assets for the Investor Class and 1.15% of net assets for Class I through the end of the fiscal year ending September 30, 2015. No termination of this agreement by either the Board of Trustees or the Adviser may be effective until, at the earliest, October 1, 2015. The Adviser is contractually obligated to waive fees or reimburse expenses in order to limit Ariel Global Equity Fund's total annual operating expenses to 1.40% of net assets for the Investor Class and 1.15% of net assets for Class I through the end of the fiscal year ending September 30, 2015. No termination of this agreement by either the Board of Trustees or the Adviser may be effective until, at the earliest, October 1, 2015. ARIEL INVESTMENT TRUST 485BPOS false 0000798365 2013-09-30 2013-01-28 2013-01-31 2013-02-01 Ariel Fund ARGFX ARAIX Fees and expenses of the Fund <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The table below describes fees and expenses that you may pay if you buy and hold shares of the Fund.</font> </div> 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0060 0.0060 0.0025 0.0000 0.0021 0.0008 0.0106 0.0068 ~ http://www.arielinvestments.com/20130128/role/ScheduleShareholderFees20001 column dei_LegalEntityAxis compact ck0000798365_S000005024Member row primary compact * ~ ~ http://www.arielinvestments.com/20130128/role/ScheduleAnnualFundOperatingExpenses20002 column dei_LegalEntityAxis compact ck0000798365_S000005024Member 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 investment strategy <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: -10.8pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; COLOR: #022847">Ariel Fund</font> <font style="DISPLAY: inline; COLOR: #403200">invests primarily in common stocks of U.S. companies and the Fund generally will have a weighted average market capitalization between $1 billion and $7.5 billion.&#160;&#160;The Fund will not hold stocks that fall within the top two quintiles of the Russell U.S. equity indexes (a comprehensive representation of market-cap weighted security indexes of the investable U.S. equity market) and if such stock falls within the top two quintiles, it will be sold by the end of the following quarter.</font></font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 2.15pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">The essence of the Fund&#8217;s strategy is a combination of patience and stock selection.&#160;&#160;The Fund seeks to hold investments for a relatively long period of time&#8212;generally five years.</font> </div> <br/><div style="TEXT-INDENT: 0pt; 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height: 47px;" border="0" cellspacing="0" cellpadding="0"> <tr> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> Best Quarter : </td> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> 2Q '09 </td> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> +34.75% </td> </tr> <tr> <td style="border-bottom: navy 2px solid;"> Worst Quarter : </td> <td style="border-bottom: navy 2px solid;"> 4Q '08 </td> <td style="border-bottom: navy 2px solid;"> -34.28% </td> </tr> </table> 0.2032 0.0259 0.0687 0.1075 0.2015 0.0250 0.0641 0.0930 0.1343 0.0219 0.0599 0.0903 0.2075 0.0266 0.0690 0.1076 0.1600 0.0166 0.0710 0.0946 0.1921 0.0454 0.1020 0.1103 0.1805 0.0355 0.0950 0.1033 1986-11-06 1986-11-06 ~ http://www.arielinvestments.com/20130128/role/ScheduleAverageAnnualReturnsTransposed20005 column dei_LegalEntityAxis compact ck0000798365_S000005024Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">After tax returns are calculated using the highest historical individual federal marginal income tax rates and do not reflect the impact of state and local taxes.&#160;&#160;Actual after-tax returns depend on your tax situation and are not relevant if Fund shares are held in tax-deferred arrangements, such as Individual Retirement Accounts (IRAs).</font> </div> After tax returns are calculated using the highest historical individual federal marginal income tax rates and do not reflect the impact of state and local taxes. The Fund's past performance, before and after taxes, is not necessarily an indication of its future performance. arielinvestments.com Actual after-tax returns depend on your tax situation and are not relevant if Fund shares are held in tax-deferred arrangements, such as Individual Retirement Accounts (IRAs). The bar chart and the table below show two aspects of the Fund: variability and performance. (reflects no deductions for fees, expenses or taxes) 800.292.7435 Average Annual Total Returns Principal risks <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">Although Ariel makes every effort to achieve the Fund&#8217;s objective of long-term capital appreciation, Ariel cannot guarantee it will attain that objective.&#160;&#160;You could lose money by investing in this Fund.&#160;&#160;The principal risks are:</font> </div> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td align="left" valign="top" width="4%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: wingdings; COLOR: #000080; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: wingdings">v</font></font> </div> </td> <td align="left" valign="top" width="83%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">Small and medium capitalization stocks held by the Fund could fall out of favor and returns would subsequently trail returns from the overall stock market.&#160;&#160;The performance of such stocks could also be more volatile.</font> </div> </td> </tr> </table> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td align="left" valign="top" width="4%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: wingdings; COLOR: #000080; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: wingdings">v</font></font> </div> </td> <td align="left" valign="top" width="83%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The general level of stock prices could decline.</font> </div> </td> </tr> </table> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td align="left" valign="top" width="4%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: wingdings; COLOR: #000080; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: wingdings">v</font></font> </div> </td> <td align="left" valign="top" width="83%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The Fund often invests a significant portion of its assets in companies within the financial services and consumer discretionary sectors and its performance may suffer if these sectors underperform the overall stock market.</font> </div> </td> </tr> </table> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">You should consider investing in the Fund if you are looking for long-term capital appreciation and are willing to accept the associated risks.</font> </div> You could lose money by investing in this Fund. <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">The example below illustrates the expenses you would pay on a $10,000 investment in Ariel Fund.&#160;&#160;It assumes the Fund earned an annual return of 5% each year, the Fund&#8217;s operating expenses remain the same and that you redeem your shares at the end of each time period. The example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.&#160;&#160;Your actual expenses may be greater or less than the amounts shown.</font> </div> 108 337 585 1294 69 218 379 847 ~ http://www.arielinvestments.com/20130128/role/ScheduleExpenseExampleTransposed20003 column dei_LegalEntityAxis compact ck0000798365_S000005024Member row primary compact * ~ Investment objective <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">Ariel Fund pursues long-term capital appreciation by investing in undervalued companies that show strong potential for growth.</font> </div> Portfolio turnover <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or &#8220;turns over&#8221; its portfolio).&#160;&#160;Higher turnover rates may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account.&#160;&#160;These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund&#8217;s performance.&#160;&#160;During the most recent fiscal year, the Fund&#8217;s portfolio turnover rate was 27% of the average value of its portfolio.</font> </div> 0.27 Ariel Appreciation Fund CAAPX CAAIX Fees and expenses of the Fund <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The table below describes fees and expenses that you may pay if you buy and hold shares of the Fund.</font> </div> 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0071 0.0071 0.0025 0.0000 0.0021 0.0028 0.0117 0.0099 ~ http://www.arielinvestments.com/20130128/role/ScheduleShareholderFees20008 column dei_LegalEntityAxis compact ck0000798365_S000005025Member row primary compact * ~ ~ http://www.arielinvestments.com/20130128/role/ScheduleAnnualFundOperatingExpenses20009 column dei_LegalEntityAxis compact ck0000798365_S000005025Member 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 investment strategy <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">Ariel Appreciation Fund invests primarily in common stocks of U.S. companies and the Fund generally will have a weighted average market capitalization between $2 billion and $15 billion.&#160;&#160;The Fund will not hold stocks that fall within the top quintile of the Russell U.S. equity indexes (a comprehensive representation of market-cap weighted security indexes of the investable U.S. equity market) and if such stock falls within the top quintile, it will be sold by the end of the following quarter.</font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">The essence of the Fund&#8217;s strategy is a combination of patience and stock selection.&#160;&#160;The Fund seeks to hold investments for a relatively long period of time&#8212;generally five years.</font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">The Fund seeks to invest in quality companies in industries in which the Adviser has expertise including the financial services and consumer discretionary sectors.&#160;&#160;The Fund only buys when Ariel believes that these businesses are selling at excellent values.</font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">Quality companies typically share several attributes that Ariel believes will result in capital appreciation over time: high barriers to entry, sustainable competitive advantages, predictable fundamentals that allow for double-digit earnings growth, skilled management teams and solid financials.&#160;&#160;Ariel&#8217;s strategy to focus on a limited number of names and industries is designed to add value in areas in which it has expertise.&#160;&#160;We believe this approach creates a portfolio of well-researched stocks.&#160;&#160;As disciplined value investors, we make opportunistic purchases when great companies are temporarily out of favor&#8212;generally seeking to invest in companies that are trading at a low valuation relative to potential earnings and/or a low valuation relative to intrinsic worth.&#160;&#160;We will sell a stock if its valuation reaches our private market value, as determined by the Adviser, if a better opportunity for investment presents itself, or if there are material changes to a company&#8217;s fundamentals.</font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">The Fund does not invest in corporations whose primary source of revenue is derived from the production or sale of tobacco products or the manufacture of handguns.&#160;&#160;We believe these industries are more likely to face shrinking growth prospects, draining litigation costs and legal liability that cannot be quantified.</font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; COLOR: #403200">Ariel Appreciation Fund is a diversified fund that will generally hold between 30&#8211;50 securities in its portfolio</font><font style="DISPLAY: inline; COLOR: #938971">.</font></font> </div> Performance <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-SIZE: 10pt">The bar chart and the table&#160;show two aspects of the Fund: variability and performance.&#160;&#160;The bar chart shows the variability of the Fund&#8217;s Investor Class annual total returns over time by showing changes in the Fund&#8217;s Investor Class performance from year to year.&#160;&#160;The table shows the Fund&#8217;s average annual total returns for certain time periods compared to the returns of the S&amp;P 500 Index, a broad measure of market performance, and indices that reflect the market sectors in which the Fund invests.&#160;&#160;The bar chart and table provide some indication of the risks of investing in the Fund.&#160;&#160;To obtain updated performance information, visit the Fund&#8217;s website at arielinvestments.com or call 800.292.7435.&#160;&#160;The Fund&#8217;s past performance, before and after taxes, is not necessarily an</font> indication of its future performance.</font> </div> Total Return for the Year Ended December 31 0.3097 0.1310 0.0292 0.1094 -0.0140 -0.4074 0.6296 0.1961 -0.0735 0.1935 ~ http://www.arielinvestments.com/20130128/role/ScheduleAnnualTotalReturnsBarChart20011 column dei_LegalEntityAxis compact ck0000798365_S000005025Member row primary compact * ~ Best Quarter: 0.2974 2009-06-30 Worst Quarter: -0.2988 2008-12-31 <table style="width: 238px; height: 47px;" border="0" cellspacing="0" cellpadding="0"> <tr> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> Best Quarter : </td> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> 2Q '09 </td> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> +29.74% </td> </tr> <tr> <td style="border-bottom: navy 2px solid;"> Worst Quarter : </td> <td style="border-bottom: navy 2px solid;"> 4Q '08 </td> <td style="border-bottom: navy 2px solid;"> -29.88% </td> </tr> </table> 0.1935 0.0502 0.0786 0.1024 0.1733 0.0414 0.0702 0.0903 0.1500 0.0403 0.0673 0.0876 0.1962 0.0506 0.0788 0.1025 0.1600 0.0166 0.0710 0.0857 0.1851 0.0379 0.1063 0.1102 0.1728 0.0357 0.1065 0.1072 1989-12-01 1989-12-01 ~ http://www.arielinvestments.com/20130128/role/ScheduleAverageAnnualReturnsTransposed20012 column dei_LegalEntityAxis compact ck0000798365_S000005025Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">After tax returns are calculated using the highest historical individual federal marginal income tax rates and do not reflect the impact of state and local taxes.&#160;&#160;Actual after-tax returns depend on your tax situation and are not relevant if Fund shares are held in tax-deferred arrangements, such as Individual Retirement Accounts (IRAs).</font> </div> After tax returns are calculated using the highest historical individual federal marginal income tax rates and do not reflect the impact of state and local taxes. The Fund's past performance, before and after taxes, is not necessarily an indication of its future performance. arielinvestments.com Actual after-tax returns depend on your tax situation and are not relevant if Fund shares are held in tax-deferred arrangements, such as Individual Retirement Accounts (IRAs). The bar chart and the table show two aspects of the Fund: variability and performance. (reflects no deductions for fees, expenses or taxes) 800.292.7435 Average Annual Total Returns Principal risks <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">Although Ariel makes every effort to achieve the Fund&#8217;s objective of long-term capital appreciation, Ariel cannot guarantee it will attain that objective.&#160;&#160;You could lose money by investing in this Fund.&#160;&#160;The principal risks are:</font> </div> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: wingdings; COLOR: #000080; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: wingdings">v</font></font> </div> </td> <td align="left" valign="top" width="86%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">Medium capitalization stocks held by the Fund could fall out of favor and returns would subsequently trail returns from the overall stock market.&#160; The performance of such stocks could also be more volatile.</font> </div> </td> </tr> </table> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: wingdings; COLOR: #000080; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: wingdings">v</font></font> </div> </td> <td align="left" valign="top" width="86%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The general level of stock prices could decline.</font> </div> </td> </tr> </table> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: wingdings; COLOR: #000080; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: wingdings">v</font></font> </div> </td> <td align="left" valign="top" width="86%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The Fund often invests a significant portion of its assets in companies within the financial services and consumer discretionary sectors and its performance may suffer if these sectors underperform the overall stock market.</font> </div> </td> </tr> </table> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">You should consider investing in the Fund if you are looking for long-term capital appreciation and are willing to accept the associated risks.</font> </div> You could lose money by investing in this Fund. <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">The example below illustrates the expenses you would pay on a $10,000 investment in Ariel Appreciation Fund.&#160;&#160;It assumes the Fund earned an annual return of 5% each year, the Fund&#8217;s operating expenses remain the same and that you redeem your shares at the end of each time period. The example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. Your actual expenses may be greater or less than the amounts shown.</font> </div> 119 372 644 1420 101 315 547 1213 ~ http://www.arielinvestments.com/20130128/role/ScheduleExpenseExampleTransposed20010 column dei_LegalEntityAxis compact ck0000798365_S000005025Member row primary compact * ~ Investment objective <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">Ariel Appreciation Fund pursues long-term capital appreciation by investing in undervalued companies that show strong potential for growth.</font> </div> Portfolio turnover <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or &#8220;turns over&#8221; its portfolio).&#160;&#160;Higher turnover rates may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account.&#160;&#160;These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund&#8217;s performance.&#160;&#160;During the most recent fiscal year, the Fund&#8217;s portfolio turnover rate was 28% of the average value of its portfolio.</font> </div> 0.28 Ariel Focus Fund ARFFX AFOYX Fees and expenses of the Fund <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The table below describes fees and expenses that you may pay if you buy and hold shares of the Fund.</font><br /> &#160; </div> 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0075 0.0075 0.0025 0.0000 0.0058 0.0054 0.0158 0.0129 -0.0033 -0.0029 0.0125 0.0100 ~ http://www.arielinvestments.com/20130128/role/ScheduleShareholderFees20015 column dei_LegalEntityAxis compact ck0000798365_S000005026Member row primary compact * ~ ~ http://www.arielinvestments.com/20130128/role/ScheduleAnnualFundOperatingExpenses20016 column dei_LegalEntityAxis compact ck0000798365_S000005026Member row primary compact * ~ 2014-09-30 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 investment strategy <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">Ariel Focus Fund invests primarily in common stocks of companies of any size in order to provide investors access to the best opportunities in companies of all market capitalizations.&#160;&#160;The essence of the Fund&#8217;s strategy is a combination of patience and stock selection.&#160;&#160;The Fund seeks to hold investments for a relatively long period of time&#8212;generally five years.&#160;&#160;&#160;&#160;The Fund invests primarily in high quality companies that are trading at low multiples of their actual or projected earnings.&#160;&#160;The Fund only buys when Ariel believes that these businesses are selling at excellent values.</font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">Quality companies typically share several attributes that Ariel believes will result in capital appreciation over time: high barriers to entry, sustainable competitive advantages, predictable fundamentals that allow for double digit earnings growth, skilled management teams and solid financials.&#160;&#160;Ariel&#8217;s strategy to focus on a limited number of names and industries is designed to add value in areas in which it has expertise.&#160;&#160;We believe this approach creates a portfolio of well-researched stocks.&#160;&#160;As disciplined value investors, we make opportunistic purchases when great companies are temporarily out of favor&#8212;generally seeking to invest in companies that are trading at a low valuation relative to potential earnings and/or a low valuation relative to intrinsic worth.&#160;&#160;We will sell a stock if its valuation reaches our private market value, as determined by the Adviser, if a better opportunity for investment presents itself, or if there are material changes to a company&#8217;s fundamentals.</font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">The Fund does not invest in corporations whose primary source of revenue is derived from the production or sale of tobacco products or the manufacture of handguns.&#160;&#160;We believe these industries are more likely to face shrinking growth prospects, draining litigation costs and legal liability that cannot be quantified.</font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">Ariel Focus Fund is a non-diversified fund, which means that the Fund could own as few as 12 securities in its portfolio, and will generally own 25&#8211;30 securities.</font> </div> Performance <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The bar chart and the table below show two aspects of the Fund: variability and performance.&#160;&#160;The bar chart shows the variability of the Fund&#8217;s Investor Class annual total returns over time by showing changes in the Fund&#8217;s Investor Class performance from year to year.&#160;&#160;The table shows the Fund&#8217;s average annual total returns for certain time periods compared to the returns of the S&amp;P 500 Index, a broad measure of market performance, and indices that reflect the market sectors in which the Fund invests.&#160;&#160;The bar chart and table provide some indication of the risks of investing in the Fund.&#160;&#160;To obtain updated performance information, visit the Fund&#8217;s website at arielinvestments.com or call 800.292.7435.&#160;&#160;The Fund&#8217;s past performance, before and after taxes, is not necessarily an indication of its future performance.</font> </div> Total Return for the Year Ended December 31 0.1158 -0.0254 -0.3509 0.3346 0.1113 -0.0521 0.1142 ~ http://www.arielinvestments.com/20130128/role/ScheduleAnnualTotalReturnsBarChart20018 column dei_LegalEntityAxis compact ck0000798365_S000005026Member row primary compact * ~ Best Quarter: 0.2287 2009-06-30 Worst Quarter: -0.2682 2008-12-31 <table style="width: 238px; height: 47px;" border="0" cellspacing="0" cellpadding="0"> <tr> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> Best Quarter : </td> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> 2Q '09 </td> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> +22.87% </td> </tr> <tr> <td style="border-bottom: navy 2px solid;"> Worst Quarter : </td> <td style="border-bottom: navy 2px solid;"> 4Q '08 </td> <td style="border-bottom: navy 2px solid;"> -26.82% </td> </tr> </table> 0.1142 0.0033 0.0210 0.1122 0.0024 0.0191 0.0768 0.0027 0.0176 0.1165 0.00389 0.0213 0.1600 0.0166 0.0462 0.1751 0.0059 0.0379 2005-06-30 2005-06-30 ~ http://www.arielinvestments.com/20130128/role/ScheduleAverageAnnualReturnsTransposed20019 column dei_LegalEntityAxis compact ck0000798365_S000005026Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">After tax returns are calculated using the highest historical individual federal marginal income tax rates and do not reflect the impact of state and local taxes.&#160;&#160;Actual after-tax returns depend on your tax situation and are not relevant if Fund shares are held in tax-deferred arrangements, such as Individual Retirement Accounts (IRAs).</font> </div> After tax returns are calculated using the highest historical individual federal marginal income tax rates and do not reflect the impact of state and local taxes. The Fund's past performance, before and after taxes, is not necessarily an indication of its future performance. arielinvestments.com Actual after-tax returns depend on your tax situation and are not relevant if Fund shares are held in tax-deferred arrangements, such as Individual Retirement Accounts (IRAs). The bar chart and the table below show two aspects of the Fund: variability and performance. (reflects no deductions for fees, expenses or taxes) 800.292.7435 Average Annual Total Returns Principal risks <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">Although Ariel makes every effort to achieve the Fund&#8217;s objective of long-term capital appreciation, Ariel cannot guarantee it will attain that objective.&#160;&#160;You could lose money by investing in this Fund.&#160;&#160;The principal risks of investing in the Fund are:</font> </div> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: wingdings; COLOR: #022847; FONT-SIZE: 10pt; FONT-WEIGHT: bold">v</font> </div> </td> <td align="left" valign="top" width="84%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">As the Fund holds relatively few stocks, a fluctuation in one stock could significantly affect overall performance.</font> </div> </td> </tr> </table> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: wingdings; COLOR: #022847; FONT-SIZE: 10pt; FONT-WEIGHT: bold">v</font> </div> </td> <td align="left" valign="top" width="97%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">Small and medium capitalization stocks held by the Fund could fall out of favor and returns would subsequently trail returns&#160;from the overall stock market.&#160;&#160;The performance of such stocks could also be more volatile.</font> </div> </td> </tr> </table> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: wingdings; COLOR: #022847; FONT-SIZE: 10pt; FONT-WEIGHT: bold">v</font> </div> </td> <td align="left" valign="top" width="84%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The general level of stock prices could decline.</font> </div> </td> </tr> </table> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">You should consider investing in the Fund if you are looking for long-term capital appreciation and are willing to accept the associated risks.</font> </div> You could lose money by investing in this Fund. <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">The example below illustrates the expenses you would pay on a $10,000 investment in Ariel Focus Fund.&#160;&#160;It assumes the Fund earned an annual return of 5% each year, the Fund&#8217;s operating expenses remain the same and that you redeem your shares at the end of each time period.&#160;&#160;The example reflects contractual fee waivers and expense reimbursements through September 30, 2014.&#160;&#160;The example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.&#160;&#160;Your actual expenses may be greater or less than the amounts shown.</font> </div> 127 432 796 1821 102 350 650 1504 ~ http://www.arielinvestments.com/20130128/role/ScheduleExpenseExampleTransposed20017 column dei_LegalEntityAxis compact ck0000798365_S000005026Member row primary compact * ~ Investment objective <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">Ariel Focus Fund pursues long-term capital appreciation by investing in undervalued companies that show strong potential for growth.</font> </div> Portfolio turnover <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or &#8220;turns over&#8221; its portfolio).&#160;&#160;Higher turnover rates may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account.&#160;&#160;These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund&#8217;s performance.&#160;&#160;During the most recent fiscal year, the Fund&#8217;s portfolio turnover rate was 32% of the average value of its portfolio.</font> </div> 0.32 Ariel Discovery Fund ARDFX ADYIX Fees and expenses of the Fund <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The table below describes fees and expenses that you may pay if you buy and hold shares of the Fund.</font> </div> 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0100 0.0100 0.0025 0.0000 0.0393 0.0378 0.0518 0.0478 -0.0368 -0.0353 0.0150 0.0125 ~ http://www.arielinvestments.com/20130128/role/ScheduleShareholderFees20022 column dei_LegalEntityAxis compact ck0000798365_S000031125Member row primary compact * ~ ~ http://www.arielinvestments.com/20130128/role/ScheduleAnnualFundOperatingExpenses20023 column dei_LegalEntityAxis compact ck0000798365_S000031125Member row primary compact * ~ 2014-09-30 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 investment strategy <div style="TEXT-INDENT: 0pt; 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DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">The Fund does not invest in corporations whose primary source of revenue is derived from the production or sale of tobacco products or the manufacture of handguns.&#160;&#160;We believe these industries are more likely to face shrinking growth prospects, draining litigation costs and legal liability that cannot be quantified.</font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">Ariel Discovery Fund is a diversified fund that generally will not hold more than 50 securities in its portfolio.</font> </div> Performance <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The bar chart and the table below show two aspects of the Fund: variability and performance.&#160;&#160;The bar chart shows the variability of the Fund&#8217;s Investor Class annual total returns over time by showing changes in the Fund&#8217;s Investor Class performance from year to year.&#160;&#160;The table shows the Fund&#8217;s average annual total returns for certain time periods compared to the returns of the S&amp;P 500 Index, a broad measure of market performance, and indices that reflect the market sectors in which the Fund invests.&#160;&#160;The bar chart and table provide some indication of the risks of investing in the Fund.&#160;&#160;To obtain updated performance information, visit the Fund&#8217;s website at arielinvestments.com or call 800.292.7435.&#160;&#160;The Fund&#8217;s past performance, before and after taxes, is not necessarily an indication of its future performance.</font> </div> Total Return for the Year Ended December 31 0.1565 ~ http://www.arielinvestments.com/20130128/role/ScheduleAnnualTotalReturnsBarChart20025 column dei_LegalEntityAxis compact ck0000798365_S000031125Member row primary compact * ~ Best Quarter: 0.1132 2012-03-31 Worst Quarter: -0.0198 2012-12-31 <table style="width: 238px; height: 47px;" border="0" cellspacing="0" cellpadding="0"> <tr> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> Best Quarter : </td> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> 1Q '12 </td> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> +11.32% </td> </tr> <tr> <td style="border-bottom: navy 2px solid;"> Worst Quarter : </td> <td style="border-bottom: navy 2px solid;"> 4Q '12 </td> <td style="border-bottom: navy 2px solid;"> -1.98% </td> </tr> </table> 0.1565 0.0217 0.1565 0.0217 0.1017 0.0185 0.1609 0.1605 0.1600 0.0792 0.1805 0.0585 2011-01-31 2011-01-31 ~ http://www.arielinvestments.com/20130128/role/ScheduleAverageAnnualReturnsTransposed20026 column dei_LegalEntityAxis compact ck0000798365_S000031125Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ The Fund's past performance, before and after taxes, is not necessarily an indication of its future performance. arielinvestments.com The bar chart and the table below show two aspects of the Fund: variability and performance. (reflects no deductions for fees, expenses or taxes) 800.292.7435 Average Annual Total Returns Principal risks <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; COLOR: #403200">Although Ariel makes every effort to achieve the Fund&#8217;s objective of long-term capital appreciation, Ariel cannot</font><font style="DISPLAY: inline; COLOR: #938971">&#160;</font><font style="DISPLAY: inline; COLOR: #403200">guarantee it will attain that objective.&#160;&#160;You could lose money by investing in this Fund.&#160;&#160;The principal risks are:</font></font> </div> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: wingdings; COLOR: #022847; FONT-SIZE: 10pt; FONT-WEIGHT: bold">v</font> </div> </td> <td align="left" valign="top" width="86%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">Small capitalization stocks held by the Fund could fall out of favor and returns would subsequently trail returns from the overall stock market.&#160; The performance of such stocks could also be more volatile. Small capitalization companies often have less predictable earnings, more limited product lines and markets and more limited financial and management resources.</font> </div> </td> </tr> </table> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: wingdings; COLOR: #022847; FONT-SIZE: 10pt; FONT-WEIGHT: bold">v</font> </div> </td> <td align="left" valign="top" width="97%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The general level of stock prices could decline.</font> </div> </td> </tr> </table> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">You should consider investing in the Fund if you are looking for long-term capital appreciation and are willing to accept the associated risks.</font> </div> You could lose money by investing in this Fund. <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">The example below illustrates the expenses you would pay on a $10,000 investment in Ariel Discovery Fund.&#160;&#160;It assumes the Fund earned an annual return of 5% each year, the Fund&#8217;s operating expenses remain the same and that you redeem your shares at the end of each time period.&#160;&#160;The example reflects contractual fee waivers and expense reimbursements through September 30, 2014.&#160;&#160;The example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.&#160;&#160;Your actual expenses may be greater or less than the amounts shown.</font> </div> 153 471 1577 4324 127 394 1428 4032 ~ http://www.arielinvestments.com/20130128/role/ScheduleExpenseExampleTransposed20024 column dei_LegalEntityAxis compact ck0000798365_S000031125Member row primary compact * ~ Investment objective <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">Ariel Discovery Fund pursues long-term capital appreciation.</font> </div> Portfolio turnover <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or &#8220;turns over&#8221; its portfolio).&#160;&#160;Higher turnover rates may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account.&#160;&#160;These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund&#8217;s performance.&#160;&#160;During the most recent fiscal year, the Fund&#8217;s portfolio turnover rate was 33% of the average value of its portfolio.</font> </div> 0.33 Ariel International Equity Fund AINTX AINIX Fees and expenses of the Fund <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The table below describes fees and expenses that you may pay if you buy and hold shares of the Fund.</font> </div> 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0100 0.0100 0.0025 0.0000 0.1575 0.1470 0.1700 0.1570 -0.1560 -0.1455 0.0140 0.0115 ~ http://www.arielinvestments.com/20130128/role/ScheduleShareholderFees20029 column dei_LegalEntityAxis compact ck0000798365_S000035291Member row primary compact * ~ ~ http://www.arielinvestments.com/20130128/role/ScheduleAnnualFundOperatingExpenses20030 column dei_LegalEntityAxis compact ck0000798365_S000035291Member row primary compact * ~ 2015-09-30 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 investment strategy <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <br /> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">Ariel International Equity Fund invests primarily in common stock issued by companies outside the U.S. in developed international markets.&#160;&#160;The Fund may invest in large, medium, or small companies without regard to market capitalization.&#160;&#160;Under normal market conditions, the Fund will invest at least 80% of its assets (net assets plus any borrowings for investment purposes) in equity securities.&#160;&#160;The Fund may buy and sell currency on a spot basis and enter into foreign currency forward contracts for portfolio management.</font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">The Fund may buy or sell foreign currency options and securities, securities index options, futures contracts and related options, and enter into swap agreements, which are types of derivatives.&#160;&#160;These techniques may be used for any legally permissible purpose, including seeking to increase the Fund&#8217;s return through the use of derivatives as a substitute for securities or to reduce the risk of loss of certain holdings.&#160;&#160;The Fund may also invest in exchange traded funds (&#8220;ETFs&#8221;).</font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The Fund&#8217;s investment process seeks to identify investment opportunities offering superior risk-adjusted returns by pursuing a &#8220;bottom-up&#8221; stock picking discipline that focuses on both the fundamentals of the business and the intrinsic value of the business.&#160;&#160;Particular attention is paid to normalized cash flow generation and reinvestment or distribution for shareholder benefit.</font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">We will consider selling a stock if its valuation reaches our investment goals, if a better opportunity for investment presents itself, or if there are material adverse changes to a company&#8217;s fundamentals.</font> </div> <br/><div style="TEXT-INDENT: 0pt; 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height: 47px;" border="0" cellspacing="0" cellpadding="0"> <tr> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> Best Quarter : </td> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> 4Q '12 </td> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> +6.79% </td> </tr> <tr> <td style="border-bottom: navy 2px solid;"> Worst Quarter : </td> <td style="border-bottom: navy 2px solid;"> 2Q '12 </td> <td style="border-bottom: navy 2px solid;"> -11.41% </td> </tr> </table> 0.0434 0.0432 0.0434 0.0432 0.0321 0.0384 0.0460 0.0458 0.1790 0.1785 2011-12-30 2011-12-30 ~ http://www.arielinvestments.com/20130128/role/ScheduleAverageAnnualReturnsTransposed20033 column dei_LegalEntityAxis compact ck0000798365_S000035291Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ The Fund's past performance, before and after taxes, is not necessarily an indication of its future performance. arielinvestments.com The bar chart and the table below show two aspects of the Fund: variability and performance. (reflects no deductions for fees, expenses or taxes) 800.292.7435 Average Annual Total Returns Principal risks <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">Although Ariel makes every effort to achieve the Fund&#8217;s objective of long-term capital appreciation, Ariel cannot guarantee it will attain that objective.&#160;&#160;You could lose money by investing in this Fund.&#160;&#160;The principal risks are:</font> </div> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: wingdings; COLOR: #022847; FONT-SIZE: 10pt; FONT-WEIGHT: bold">v</font> </div> </td> <td align="left" valign="top" width="86%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The general level of stock prices could decline.</font> </div> </td> </tr> </table> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: wingdings; COLOR: #022847; FONT-SIZE: 10pt; FONT-WEIGHT: bold">v</font> </div> </td> <td align="left" valign="top" width="86%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">Investments in foreign securities may underperform and may be more volatile than comparable U.S. stocks.&#160; Foreign economies and markets may not be as strong or well regulated, foreign political systems may not be as stable, and foreign financial reporting and disclosure standards may not be as rigorous as those in the U.S.</font> </div> </td> </tr> </table> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: wingdings; COLOR: #022847; FONT-SIZE: 10pt; FONT-WEIGHT: bold">v</font> </div> </td> <td align="left" valign="top" width="86%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">Securities issued by foreign companies are typically denominated in foreign currencies, resulting in a risk that adverse exchange rate fluctuations against the U.S. dollar could create losses and could depress prices for extended periods of time.&#160; The use of foreign currency derivatives may be expensive and may result in further losses.</font> </div> </td> </tr> </table> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: wingdings; COLOR: #022847; FONT-SIZE: 10pt; FONT-WEIGHT: bold">v</font> </div> </td> <td align="left" valign="top" width="86%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The use of various types of derivatives may intensify investment losses from securities underlying the derivatives, may create more volatility and may expose the Fund to other losses and expenses. 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FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: wingdings; COLOR: #022847; FONT-SIZE: 10pt; FONT-WEIGHT: bold">v</font> </div> </td> <td align="left" valign="top" width="86%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">Small and medium capitalization stocks held by the Fund could fall out of favor and returns would subsequently trail returns from the overall stock market.&#160; The performance of such stocks could also be more volatile.</font> </div> </td> </tr> </table> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"><font style="DISPLAY: inline; FONT-SIZE: 10pt">&#160;</font><font style="DISPLAY: inline; COLOR: #403200">You should consider investing in the Fund if you are looking for long-term capital appreciation and are willing to accept the associated risks.</font></font> </div> You could lose money by investing in this Fund. <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">The example below illustrates the expenses you would pay on a $10,000 investment in Ariel International Equity Fund.&#160;&#160;It assumes the Fund earned an annual return of 5% each year, the Fund&#8217;s operating expenses remain the same and that you redeem your shares at the end of each time period.&#160;&#160;The example reflects contractual fee waivers and expense reimbursements through September 30, 2015.&#160;&#160;The example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.&#160;&#160;Your actual expenses may be greater or less than the amounts shown.</font> </div> 143 443 3784 9199 117 365 3516 8876 ~ http://www.arielinvestments.com/20130128/role/ScheduleExpenseExampleTransposed20031 column dei_LegalEntityAxis compact ck0000798365_S000035291Member row primary compact * ~ Investment objective <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; COLOR: #403200; FONT-SIZE: 10pt">Ariel International Equity Fund pursues long-term capital appreciation.</font> </div> Portfolio turnover <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; COLOR: #403200; FONT-SIZE: 10pt">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or &#8220;turns over&#8221; its portfolio).&#160;&#160;Higher turnover rates may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account.&#160;&#160;These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund&#8217;s performance.&#160;&#160;During the most recent fiscal period, the Fund&#8217;s portfolio turnover rate was 21% of the average value of its portfolio.</font> </div> 0.21 Ariel Global Equity Fund AGLOX AGLYX Fees and expenses of the Fund <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">The table below describes fees and expenses that you may pay if you buy and hold shares of the Fund.</font><br /> <font style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt">&#160;</font> </div> 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0100 0.0100 0.0025 0.0000 0.1108 0.0307 0.1233 0.0407 -0.1093 -0.0292 0.0140 0.0115 ~ http://www.arielinvestments.com/20130128/role/ScheduleShareholderFees20036 column dei_LegalEntityAxis compact ck0000798365_S000035292Member row primary compact * ~ ~ http://www.arielinvestments.com/20130128/role/ScheduleAnnualFundOperatingExpenses20037 column dei_LegalEntityAxis compact ck0000798365_S000035292Member row primary compact * ~ 2015-09-30 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 investment strategy <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">Ariel Global Equity Fund invests primarily in common stock issued by companies both within and outside the U.S., including in countries with developed or emerging markets.&#160;&#160;The Fund may invest in large, medium, or small companies without regard to market capitalization.&#160;&#160;Under normal market conditions, the Fund will invest at least 80% of its assets (net assets plus any borrowings for investment purposes) in equity securities and at least 40% of its assets in countries other than the U.S.&#160;&#160;The Fund may buy and sell currency on a spot basis and enter into foreign currency forward contracts for portfolio management.</font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">The Fund may buy or sell foreign currency options and securities, securities index options, futures contracts and related options, and enter into swap agreements, which are types of derivatives.&#160;&#160;These techniques may be used for any legally permissible purpose, including seeking to increase the Fund&#8217;s return through the use of derivatives as a substitute for securities or to reduce the risk of loss of certain holdings.&#160;&#160;The Fund may also invest in exchange traded funds (&#8220;ETFs&#8221;).</font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">The Fund&#8217;s investment process seeks to identify investment opportunities offering superior risk-adjusted returns by pursuing a &#8220;bottom-up&#8221; stock picking discipline that focuses on both the fundamentals of the business and the intrinsic value of the business.&#160;&#160;Particular attention is paid to normalized cash flow generation and reinvestment or distribution for shareholder benefit.</font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">We will consider selling a stock if its valuation reaches our investment goals, if a better opportunity for investment presents itself, or if there are material adverse changes to a company&#8217;s fundamentals.</font> </div> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">Ariel Global Equity Fund is a diversified fund that will generally hold between 40-150 securities in its portfolio.</font> </div> \Performance <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">The bar chart and the table below show two aspects of the Fund: variability and performance.&#160;&#160;The bar chart shows the variability of the Fund&#8217;s Investor Class annual total returns over time by showing changes in the Fund&#8217;s Investor Class performance from year to year.&#160;&#160;The table shows the Fund&#8217;s average annual total returns for certain time periods compared to the returns of the MSCI ACWI<font style="DISPLAY: inline; FONT-SIZE: 70%; VERTICAL-ALIGN: text-top">SM</font>, a broad measure of market performance.&#160;&#160;The bar chart and table provide some indication of the risks of investing in the Fund.&#160;&#160;To obtain updated performance information, visit the Fund&#8217;s website at arielinvestments.com or call 800.292.7435.&#160;&#160;The Fund&#8217;s past performance, before and after taxes, is not necessarily an indication of its future performance.</font> </div> Total Return for the Year Ended December 31 0.0550 ~ http://www.arielinvestments.com/20130128/role/ScheduleAnnualTotalReturnsBarChart20039 column dei_LegalEntityAxis compact ck0000798365_S000035292Member row primary compact * ~ Best Quarter: 0.0529 2012-12-31 Worst Quarter: -0.0894 2012-06-30 <table style="width: 238px; height: 47px;" border="0" cellspacing="0" cellpadding="0"> <tr> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> Best Quarter : </td> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> 4Q '12 </td> <td style="border-top: navy 2px solid; border-bottom: #99ccff 2px dashed;"> +5.29% </td> </tr> <tr> <td style="border-bottom: navy 2px solid;"> Worst Quarter : </td> <td style="border-bottom: navy 2px solid;"> 2Q '12 </td> <td style="border-bottom: navy 2px solid;"> -8.94% </td> </tr> </table> 0.0550 0.0548 0.0550 0.0548 0.0358 0.0466 0.0579 0.0577 0.1680 0.1675 2011-12-30 2011-12-30 ~ http://www.arielinvestments.com/20130128/role/ScheduleAverageAnnualReturnsTransposed20040 column dei_LegalEntityAxis compact ck0000798365_S000035292Member column rr_PerformanceMeasureAxis compact * row primary compact * ~ The Fund's past performance, before and after taxes, is not necessarily an indication of its future performance. arielinvestments.com The bar chart and the table below show two aspects of the Fund: variability and performance. (reflects no deductions for fees, expenses or taxes) 800.292.7435 Average Annual Total Returns Principal risks <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">Although Ariel makes every effort to achieve the Fund&#8217;s objective of long-term capital appreciation, Ariel cannot guarantee it will attain that objective.&#160;&#160;You could lose money by investing in this Fund.&#160;&#160;The principal risks are:</font> </div> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: wingdings">v</font></font> </div> </td> <td align="left" valign="top" width="86%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">The general level of stock prices could decline.</font> </div> </td> </tr> </table> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: wingdings">v</font></font></font> </div> </div> </td> <td align="left" valign="top" width="86%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">Investments in foreign securities may underperform and may be more volatile than comparable U.S. stocks.&#160; Foreign economies and markets may not be as strong or well regulated, foreign political systems may not be as stable, and foreign financial reporting and disclosure standards may not be as rigorous as those in the U.S.</font> </div> </td> </tr> </table> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: wingdings">v</font></font></font> </div> </div> </td> <td align="left" valign="top" width="86%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">Investments in companies based in emerging or developing countries present risks greater than those in mature markets, including greater risk of adverse government intervention or economic turmoil, high inflation and more volatile interest and currency exchange rates.</font> </div> </td> </tr> </table> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: wingdings; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font color="#403200" style="DISPLAY: inline; FONT-FAMILY: wingdings; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font color="#403200" style="DISPLAY: inline; FONT-FAMILY: wingdings; FONT-SIZE: 10pt">v</font></font></font> </div> </div> </td> <td align="left" valign="top" width="86%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">Securities issued by foreign companies are typically denominated in foreign currencies, resulting in a risk that adverse exchange rate fluctuations against the U.S. dollar could create losses and could depress prices for extended periods of time.&#160; The use of foreign currency derivatives may be expensive and may result in further losses.</font> </div> </td> </tr> </table> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: wingdings">v</font></font></font></font> </div> </div> </div> </td> <td align="left" valign="top" width="86%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">The use of various types of derivatives may intensify investment losses from securities underlying the derivatives, may create more volatility and may expose the Fund to other losses and expenses. Certain derivatives, such as swap transactions, may entail the risk that a counterparty or party will default on payment or other obligations under the derivative.</font> </div> </td> </tr> </table> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font style="DISPLAY: inline; FONT-FAMILY: wingdings">v</font></font></font> </div> </div> </td> <td align="left" valign="top" width="86%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">ETFs may be less liquid and subsequently more volatile than the underlying portfolio of securities.&#160; ETFs also have management fees that increase the cost compared to owning the underlying securities directly.</font> </div> </td> </tr> </table> <br/><table cellpadding="0" cellspacing="0" width="100%" style="FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"> <tr> <td valign="top" width="3%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="center"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font color="#403200" style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"><font color="#403200" style="DISPLAY: inline; FONT-FAMILY: wingdings; FONT-SIZE: 10pt">v</font></font></font> </div> </div> </td> <td align="left" valign="top" width="86%"> <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: times new roman; FONT-SIZE: 10pt">Small and medium capitalization stocks held by the Fund could fall out of favor and returns would subsequently trail returns from the overall stock market.&#160; The performance of such stocks could also be more volatile.</font> </div> </td> </tr> </table> <br/><div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">You should consider investing in the Fund if you are looking for long-term capital appreciation and are willing to accept the associated risks.</font> </div> You could lose money by investing in this Fund. <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">The example below illustrates the expenses you would pay on a $10,000 investment in Ariel Global Equity Fund.&#160;&#160;It assumes the Fund earned an annual return of 5% each year, the Fund&#8217;s operating expenses remain the same and that you redeem your shares at the end of each time period.&#160;&#160;The example reflects contractual fee waivers and expense reimbursements through September 30, 2015.&#160;&#160;The example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.&#160;&#160;Your actual expenses may be greater or less than the amounts shown.</font> </div> 143 443 2988 7886 117 365 1286 3662 ~ http://www.arielinvestments.com/20130128/role/ScheduleExpenseExampleTransposed20038 column dei_LegalEntityAxis compact ck0000798365_S000035292Member row primary compact * ~ Investment objective <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">Ariel Global Equity Fund pursues long-term capital appreciation.</font> </div> Portfolio turnover <div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"> <font color="#403200" style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt">The Fund pays transaction costs, such as commissions, when it buys and sells securities (or &#8220;turns over&#8221; its portfolio).&#160;&#160;Higher turnover rates may indicate higher transaction costs and may result in higher taxes when shares are held in a taxable account.&#160;&#160;These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund&#8217;s performance.&#160;&#160;During the most recent fiscal period, the Fund&#8217;s portfolio turnover rate was 26% of the average value of its portfolio.</font> </div> 0.26