- Mutual Fund Summary Prospectus (497K)

Summary Prospectus April 29, 2011

[DWS INVESTMENTS LOGO]
Deutsche Bank Group

DWS S&P 500 INDEX FUND

CLASS/Ticker A SXPAX B SXPBX C SXPCX S SCPIX

Before you invest, you may want to review the fund's prospectus, which contains more information about the fund and its risks. You can find the fund's prospectus, Statement of Additional Information (SAI) and other information about the fund online at https://www.dws-investments.com/mutualpros. You can also get this information at no cost by e-mailing a request to [e-mail], calling [phone] (A, B, C) and [phone] (S) or asking your financial advisor. The prospectus and SAI, both dated April 29, 2011, as may be supplemented from time to time, are incorporated by reference into this Summary Prospectus.

INVESTMENT OBJECTIVE

The fund seeks to provide investment results that, before expenses, correspond to the total return of common stocks publicly traded in the United States, as represented by the Standard & Poor's 500 Composite Stock Price Index (S&P 500 Index).

The fund invests for capital appreciation, not income; any dividend and interest income is incidental to the pursuit of its objective.

The fund is a feeder fund that invests substantially all of its assets in a "master portfolio," the DWS Equity 500 Index Portfolio ("Portfolio"), which will invest directly in securities and other instruments. The Portfolio has the same investment objective as the fund. References to the fund may refer to actions undertaken by the Portfolio.

FEES AND EXPENSES OF THE FUND

These are the fees and expenses you may pay when you buy and hold shares. You may qualify for sales charge discounts if you and your immediate family invest, or agree to invest in the future, at least $100,000 in DWS funds. More information about these and other discounts is available from your financial professional and in Choosing a Share Class in the prospectus (p. 26) and Purchase and Redemption of Shares in the fund's SAI (p. II-17).

SHAREHOLDER FEES (paid directly from your investment)

A B C S ---------- --------- --------- ----- Maximum sales charge (load) imposed on purchases, as % of offering price 4.50 None None None ----------------------------------------- ---- -- -- ----- Maximum deferred sales charge (load), as % of redemption proceeds None 4.00 1.00 None ----------------------------------------- ----- ---- ---- -----

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a % of the value of your investment)

A B C S --------- --------- --------- ---------- Management fee 0.05 0.05 0.05 0.05 ---------------------------------------- ---- ---- ---- ---- Distribution/service (12b-1) fees 0.23 1.00 1.00 None ---------------------------------------- ---- ---- ---- ----- Other expenses 0.44 0.41 0.40 0.37 ---------------------------------------- ---- ---- ---- ----- TOTAL ANNUAL FUND OPERATING EXPENSES(1) 0.72 1.46 1.45 0.42 ---------------------------------------- ---- ---- ---- -----

(1) The table and the Example below reflect the expenses of both the fund and the Portfolio.

EXAMPLE

This Example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

YEARS A B C S ------- -------- -------- -------- ------ 1 $ 520 $ 549 $ 248 $43 -- ----- ----- ----- --- 3 670 762 459 135 -- ----- ----- ----- --- 5 833 997 792 235 -- ----- ----- ----- --- 10 1,304 1,361 1,735 530 -- ----- ----- ----- ---

You would pay the following expenses if you did not redeem your shares:

YEARS A B C S ------- -------- -------- -------- ------ 1 $ 520 $ 149 $ 148 $43 -- ----- ----- ----- --- 3 670 462 459 135 -- ----- ----- ----- --- 5 833 797 792 235 -- ----- ----- ----- --- 10 1,304 1,361 1,735 530 -- ----- ----- ----- ---

Class B converts to Class A after six years; the Example for Class B reflects Class A fees after the conversion.

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PORTFOLIO TURNOVER

The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover may indicate higher transaction costs and may mean higher taxes if you are investing in a taxable account. These costs are not reflected in annual fund operating expenses or in the expense example, and can affect the fund's performance.

Portfolio turnover rate for fiscal year 2010: 5%.

PRINCIPAL INVESTMENT STRATEGY

MAIN INVESTMENTS. Under normal circumstances, the Portfolio intends to invest at least 80% of assets, determined at the time of purchase, in stocks of companies included in the S&P 500 (Reg. TM) Index and in derivative instruments, such as futures contracts and options, that provide exposure to the stocks of companies in the index. The Portfolio's securities are weighted to attempt to make the Portfolio's total investment characteristics similar to those of the index as a whole. The Portfolio may also hold short-term debt securities and money market instruments.

The S&P 500 (Reg. TM) INDEX is a well-known stock market index that includes common stocks of 500 companies from several industrial sectors representing a significant portion of the market value of all stocks publicly traded in the US. Stocks in the S&P 500 (Reg. TM) Index are weighted according to their total market value. The fund is not sponsored, endorsed, sold or promoted by the Standard & Poor's (S&P) Division of The McGraw-Hill Companies, Inc.

MANAGEMENT PROCESS. Portfolio management uses quantitative analysis techniques to structure the Portfolio to seek to obtain a high correlation to the index while seeking to keep the Portfolio as fully invested as possible in all market environments. Portfolio management seeks a long-term correlation between Portfolio performance, before expenses, and the index of 98% or better (perfect correlation being 100%). The Portfolio uses an optimization strategy, buying the largest stocks in the index in approximately the same proportion they represent in the index, then investing in a statistically selected sample of the smaller securities found in the index.

DERIVATIVES. Portfolio management generally may use futures contracts, which are a type of derivative (a contract whose value is based on, for example, indices, currencies or securities), as a substitute for direct investment in a particular asset class or to keep cash on hand to meet shareholder redemptions.

The fund may also use various types of derivatives (i) for hedging purposes;
(ii) for risk management; (iii) for non-hedging purposes to seek to enhance potential gains; or (iv) as a substitute for direct investment in a particular asset class or to keep cash on hand to meet shareholder redemptions.

SECURITIES LENDING. The fund may lend securities (up to one-third of total assets) to approved institutions.

MAIN RISKS

There are several risk factors that could hurt the fund's performance, cause you to lose money or cause the fund's performance to trail that of other investments. The fund may not achieve its investment objective, and is not intended to be a complete investment program. An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency. The fund is exposed to the risk factors below even if it does not invest directly in individual securities.

STOCK MARKET RISK. The fund is affected by how the stock market performs. When stock prices fall, you should expect the value of your investment to fall as well.

INDEXING RISK. An index fund's performance may not exactly replicate the performance of its target index, for several reasons. For example, the fund incurs fees, administrative expenses and transaction costs that the index itself does not. The fund may use sampling techniques (investing in a representative selection of securities included in the index rather than all securities in the index), or the composition of its portfolio may diverge from that of the index. Also, while the exposure of the index to its component securities is by definition 100%, the fund's effective exposure to index securities may be greater or lesser than 100%, and may vary over time.

Because an index fund is designed to maintain a high level of exposure to its target index at all times, it will not take any steps to invest defensively or otherwise reduce the risk of loss during market downturns.

DERIVATIVES RISK. Risks associated with derivatives include the risk that the derivative is not well correlated with the security, index or currency to which it relates; the risk that derivatives may result in losses or missed opportunities; the risk that the fund will be unable to sell the derivative because of an illiquid secondary market; the risk that a counterparty is unwilling or unable to meet its obligation; and the risk that the derivative transaction could expose the fund to the effects of leverage, which could increase the fund's exposure to the market and magnify potential losses.

COUNTERPARTY RISK. A financial institution or other counterparty with whom the fund does business, or that underwrites, distributes or guarantees any investments or contracts that the fund owns or is otherwise exposed to, may decline in financial health and become unable to honor its commitments. This could cause losses for the fund or could delay the return or delivery of collateral or other assets to the fund.

LIQUIDITY RISK. In certain situations, it may be difficult or impossible to sell an investment in an orderly fashion at an acceptable price.

PRICING RISK. If market conditions make it difficult to value some investments, the fund may value these investments using more subjective methods, such as fair value pricing.

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DWS S&P 500 Index Fund

SUMMARY PROSPECTUS April 29, 2011

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In such cases, the value determined for an investment could be different than the value realized upon such investment's sale. As a result, you could pay more than the market value when buying fund shares or receive less than the market value when selling fund shares.

SECURITIES LENDING RISK. Any decline in the value of a portfolio security that occurs while the security is out on loan is borne by the fund, and will adversely affect performance. Also, there may be delays in recovery of securities loaned or even a loss of rights in the collateral should the borrower of the securities fail financially while holding the security.

PAST PERFORMANCE

How a fund's returns vary from year to year can give an idea of its risk; so can comparing fund performance to overall market performance (as measured by an appropriate market index). Past performance may not indicate future results. All performance figures below assume that dividends were reinvested. For more recent performance figures, go to www.dws-investments.com (the Web site does not form a part of this prospectus) or call the phone number for your share class included in this prospectus.

For Class A, B and C shares, performance prior to its inception date is based on the historical performance of the fund's original share class (Class S), each adjusted to reflect the higher net expenses of the relevant share class.

CALENDAR YEAR TOTAL RETURNS (%) (Class S)

These year-by-year returns do not include sales charges, and would be lower if they did. Returns for other classes were different and are not shown here.

[BAR GRAPHIC OMITTED HERE]

[BAR GRAPHIC DATA]

2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 -12.32 -22.33 28.04 10.37 4.47 15.37 5.22 -37.25 26.14 14.81

Best Quarter: 15.83%, Q2 2009 Worst Quarter: -21.95%, Q4 2008 Year-to-Date as of 3/31/2011: 5.79%

AVERAGE ANNUAL TOTAL RETURNS
(For periods ended 12/31/2010 expressed as a %)

After-tax returns (which are shown only for Class S and would be different for other classes) reflect the highest historical individual federal income tax rates, but do not reflect any state or local taxes. Your actual after-tax returns may be different. After-tax returns are not relevant to shares held in an IRA, 401(k) or other tax-advantaged investment plan.

CLASS 1 5 10 INCEPTION YEAR YEARS YEARS ----------- --------- --------- --------- CLASS A before tax 2/15/2005 9.31 0.74 0.33 --------------------------- --------- ----- ---- ---- CLASS B before tax 2/15/2005 10.66 0.73 0.34 --------------------------- --------- ----- ---- ---- CLASS C before tax 2/15/2005 13.63 0.92 0.04 --------------------------- --------- ----- ---- ---- CLASS S before tax 8/29/1997 14.81 1.98 1.04 --------------------------- --------- ----- ---- ---- After tax on distributions 14.81 1.82 0.80 After tax on distribu- tions and sale of fund shares 10.25 1.78 0.86 --------------------------- --------- ----- ---- ---- STANDARD & POOR'S (S&P) 500 INDEX (reflects no deduction for fees, expenses or taxes) 15.06 2.29 1.41 --------------------------- --------- ----- ---- ----

MANAGEMENT

INVESTMENT ADVISOR

Deutsche Investment Management Americas Inc.

SUBADVISOR

Northern Trust Investments, Inc.

PORTFOLIO MANAGER(S)

BRENT REEDER. Senior Vice President of Northern Trust Investments, Inc. Portfolio Manager of the fund. Joined the fund in 2007.

PURCHASE AND SALE OF FUND SHARES

MINIMUM INITIAL INVESTMENT ($)

AUTOMATIC UGMAS/ INVESTMENT NON-IRA IRAS UTMAS PLANS --------- -------- -------- ----------- A B C 1,000 500 1,000 500 ------- ----- --- ----- --- S 2,500 1,000 1,000 1,000 ------- ----- ----- ----- -----

For participants in certain fee-based and wrap programs offered through certain financial intermediaries approved by the Advisor, there is no minimum initial investment for Class A, B, C and S shares and no minimum additional investment for Class A and S shares. The minimum additional investment for all other instances is $50. For existing Class B shareholders, the minimum initial investment for Class A and C shares is $50.

TO PLACE ORDERS

MAIL First Investment DWS Investments, PO Box 219356 Kansas City, MO 64121-9356 Additional Investments DWS Investments, PO Box 219154 Kansas City, MO 64121-9154 Exchanges and DWS Investments, PO Box 219557 Redemptions Kansas City, MO 64121-9557 EXPEDITED MAIL DWS Investments, 210 West 10th Street Kansas City, MO 64105-1614 WEB SITE www.dws-investments.com TELEPHONE Class A, B or C shares: [phone] Class S shares: [phone] M - F 8 a.m. - 8 p.m. ET TDD LINE [phone], M - F 8 a.m. - 8 p.m. ET

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DWS S&P 500 Index Fund

SUMMARY PROSPECTUS April 29, 2011

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You can buy or sell shares of the fund on any business day at our web site, by mail, or by telephone. The fund is generally open on days when the New York Stock Exchange is open for regular trading.

Class B shares are closed to new purchases, except for exchanges and the reinvestment of dividends or other distributions. Class S shares are only available to a limited group of investors.

TAX INFORMATION

The fund's distributions are generally taxable to you as ordinary income or capital gains, except when your investment is in an IRA, 401(k), or other tax-deferred investment plan.

PAYMENTS TO BROKER-DEALERS AND

OTHER FINANCIAL INTERMEDIARIES

If you purchase the fund through a broker-dealer or other financial intermediary (such as a bank), the fund and its related companies may pay the intermediary for the sale of fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend

the fund over another investment. Ask your salesperson or visit your financial intermediary's web site for more information.

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DWS S&P 500 Index Fund
SUMMARY PROSPECTUS April 29, 2011 DSPIF-SUM