ProShares Hedge Replication ETF (the "Fund") seeks investment results, before fees and expenses, that track the performance of the Merrill Lynch Factor Model — Exchange Series (the "Benchmark").

The Benchmark, established by Merrill Lynch International, seeks to provide the risk and return characteristics of the hedge fund asset class by targeting a high correlation to the HFRI Fund Weighted Composite Index (the "HFRI"). The HFRI is designed to reflect hedge fund industry performance through an equally weighted composite of over 2000 constituent funds. In seeking to maintain a high correlation with the HFRI, the Benchmark utilizes a systematic model to establish, each month, weighted long or short (or, in certain cases, long or flat) positions in six underlying factors ("Factors"). The Factors that comprise the Benchmark are the (1) S&P 500^® Total Return Index, (2) the MSCI EAFE US Dollar Net Total Return Index, (3) the MSCI Emerging Markets US Dollar Net Total Return Index ("MSCI Emerging Markets"), (4) the Russell 2000 Total Return Index^® ("Russell 2000"), (5) three-month U.S. Treasury Bills, and (6) the ProShares UltraShort Euro ETF. The Benchmark is not comprised of, and the Fund does not invest in, any hedge fund or group of hedge funds.

Expense [Heading]

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Fees and Expenses of the Fund

Expense Narrative [Text Block]

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The table below describes the fees and expenses that you may pay if you buy or hold shares of the Fund ("Shares").

Operating Expenses Caption [Text]

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Annual Fund Operating Expenses

(expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination

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July 7, 2012

Portfolio Turnover [Heading]

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Portfolio Turnover

Portfolio Turnover [Text Block]

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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 result in higher taxes when Shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example above, affect the Fund's performance. The Fund's portfolio turnover rate is calculated without regard to cash instruments or derivatives whose maturities or expiration dates at the time of acquisition were one year or less. If such instruments were included, the Fund's portfolio turnover rate would be significantly higher.

Other Expenses, New Fund, Based on Estimates [Text]

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Other Expenses" are based on estimated amounts for the current fiscal year

Expense Example [Heading]

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Example:

Expense Example Narrative [Text Block]

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This example is intended to help you compare the cost of investing in Shares 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 each period. 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 cost may be higher or lower, based on these assumptions your approximate costs would be:

Expense Example Closing [Text Block]

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Investors may pay brokerage commissions on their purchases and sales of Shares, which are not reflected in the example or the table above.

Strategy [Heading]

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Principal Investment Strategies

Strategy Narrative [Text Block]

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The Fund invests in a combination of securities and derivatives that ProShare Advisors believes should track the performance of the Benchmark. It is expected that, at any given point in time, the Fund will be substantially invested in three-month U.S. Treasury Bills, which is one of the Factors, or other short-term debt instruments that have terms-to-maturity of less than 397 days and exhibit high quality credit profiles in order to gain exposure to the three-month U.S. Treasury Bill rate.

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Equity Securities — The Fund may invest in common stock issued by public companies.

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Derivatives — The Fund invests in financial instruments whose value is derived from the value of an underlying asset, interest rate or index. The Fund invests in derivatives as a substitute for investing directly in or making short sales of the securities underlying the Benchmark. Derivatives principally include:

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Swap Agreements — Contracts entered into primarily with institutional investors for a specified period ranging from a day to more than one year. In a standard "swap" transaction, two parties agree to exchange the returns (or differentials in rates of return) earned or realized on particular predetermined investments or instruments. The gross returns to be exchanged or "swapped" between the parties are calculated with respect to a "notional amount," e.g., the return on or change in value of a particular dollar amount invested in a "basket" of securities representing a particular index.

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Forward Contracts — Forward contracts are two-party contracts entered into with dealers or financial institutions where the purchase or sale of a specific quantity of a foreign currency or other financial instrument is agreed upon at a set price, with delivery and settlement at a specified future date. Forward contracts may also be structured for cash settlement, rather than physical delivery.

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Futures Contracts — Contracts that pay a fixed price for an asset or the cash value of an asset, on an agreed-upon date.

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Money Market Instruments — The Fund may invest in three-month U.S. Treasury Bills or other short-term cash instruments that have terms to maturity of less than 397 days and exhibit high quality credit profiles.

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Depositary Receipts ("DRs") — The Fund may invest in depositary receipts, which principally include:

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American Depositary Receipts (ADRs), which represent the right to receive securities of foreign issuers deposited in a bank or trust company.

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Global Depositary Receipts (GDRs), which are receipts for shares in a foreign-based corporation traded in capital markets around the world.

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New York Shares ("NYSs"), which are shares of New York registry, representing equity ownership in a non-U.S. company, allowing for a part of the capital of the company to be outstanding in the U.S. and part in the home market.

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Exchange-Traded Funds — The Fund may invest in the shares of ETFs registered under the Investment Company Act of 1940 ("1940 Act") to the extent that such investment would be consistent with the requirements of the 1940 Act, or any exemptive order issued by the SEC. The Fund may also invest in the shares of ETFs registered as commodity pools. The ETFs in which the Fund may invest may be advised by ProShare Advisors or one of its affiliates.

ProShare Advisors uses a mathematical approach to investing. Using this approach, ProShare Advisors determines the type, quantity and mix of investment positions that the Fund should hold to approximate the performance of the Benchmark. The Fund may gain exposure to only a representative sample of the securities in the Benchmark or underlying or comprising each Factor; the sample is intended to have aggregate characteristics similar to those of the Benchmark. ProShare Advisors does not invest the assets of the Fund in securities or derivatives based on ProShare Advisors' view of the investment merit of a particular security, instrument, or company, nor does it conduct conventional stock research or analysis (other than in determining counterparty creditworthiness), or forecast stock market movement or trends, in managing the assets of the Fund. The Fund seeks to remain fully invested at all times in securities (including three-month U.S. Treasury Bills and other money market instruments) and/or derivatives that provide exposure to its Benchmark without regard to market conditions, trends or direction.

Please see Investment Objective, Principal Investment Strategies, Related Risks and Disclosure of Portfolio Holdings on page 8 for additional details.

Risk [Heading]

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Principal Risks

Risk Narrative [Text Block]

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You could lose money by investing in the Fund.

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Risk Associated with the Use of Derivatives — The Fund uses investment techniques and derivatives that may be considered aggressive. Because the Fund's investment in derivatives may involve a small investment relative to the amount of investment exposure assumed, losses may exceed the amounts invested in those instruments. The use of derivatives may expose the Fund to potentially dramatic changes (losses or gains) in the value of the instruments. Using derivatives also may result in imperfect correlation between the value of the instruments and the referenced index, which may prevent the Fund from achieving its investment objective. Swap-related financing, borrowing and other costs will have the effect of lowering the Fund's return.

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Correlation Risk — A number of considerations may affect the Fund's ability to achieve a high degree of correlation with the Benchmark, and there can be no guarantee that the Fund will achieve a high degree of correlation. Failure to achieve a high degree of correlation may prevent the Fund from achieving its investment objective. The considerations that may adversely affect the Fund's correlation to the Benchmark include fees, expenses, transaction costs, costs associated with the use of derivatives and income items, as well as the fact that, on each trading day, the closing levels of the Factors within the Benchmark are calculated earlier, or in certain cases, later, than the time of valuation for the Fund. The Fund may not have investment exposure to all the Factors in the Benchmark or the securities comprising such Factors and its weighting of investment exposure to such may be different from that of the Benchmark. The Fund may be subject to large movements of assets into and out of the Fund, potentially resulting in the Fund being over- or under-exposed to the Benchmark. Activities surrounding Benchmark reconstitutions may hinder the Fund's ability to meet its investment objective.

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Counterparty Risk — The Fund will be subject to credit risk (that is, where changes in an issuer's financial strength or the credit rating of a financial instrument it issues may affect an instrument's value) with respect to the amount it expects to receive from counterparties to certain derivatives and repurchase agreements entered into by the Fund or held by special purpose or structured vehicles. If a counterparty becomes bankrupt or otherwise fails to perform its obligations due to financial difficulties, the value of your investment in the Fund may decline.

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Early Close/Late Close/Trading Halt Risk — An exchange or market may close early, close late or issue trading halts on specific securities, or the ability to buy or sell certain securities or derivatives may be restricted, which may result in the Fund being unable to buy or sell certain securities or derivatives. In such circumstances, the Fund may be unable to rebalance its portfolio, may be unable to accurately price its investments and/or may incur substantial trading losses.

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Equity and Market Risk — The equity markets are volatile, and the value of securities, swaps, futures, options contracts and other instruments correlated with the equity markets may fluctuate dramatically from day-to-day. Equity markets are subject to political, regulatory, market and economic developments, as well as developments that impact specific economic sectors, industries or segments of the market. Volatility in the markets and/or adverse market developments may cause the value of an investment in the Fund to decrease.

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Exposure to Foreign Currency Risk — Investments linked to or denominated in foreign currencies are exposed to risk factors in addition to investments denominated in U.S. dollars. The value of an investment linked to or denominated in a foreign currency could change significantly as foreign currencies strengthen or weaken relative to the U.S. dollar. Risks related to foreign currencies also include those related to economic or political developments, market inefficiencies or a higher risk that essential investment information may be incomplete, unavailable, or inaccurate. A U.S. dollar investment in Depositary Receipts or ordinary shares of foreign issuers traded on U.S. exchanges or an investment in an instrument linked to a foreign currency are subject to foreign currency risk.

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Exposure to Foreign Investments Risk — Exposure to securities of foreign issuers provide the Fund with increased risk. Various factors related to foreign investments may negatively impact the Benchmark's performance, such as: i) fluctuations in the value of the applicable foreign currency; ii) differences in securities settlement practices; iii) uncertainty associated with evidence of ownership of investments in countries that lack centralized custodial services; iv) possible regulation of, or other limitations on, investments by U.S. investors in foreign investments; v) potentially higher brokerage commissions; vi) the possibility that a foreign government may withhold portions of interest and dividends at the source; vii) taxation of income earned in foreign countries or other foreign taxes imposed; viii) foreign exchange controls, which may include suspension of the ability to transfer currency from a foreign country; ix) less publicly available information about foreign issuers; and x) less certain legal systems in which the Fund might encounter difficulties or be unable to pursue legal remedies. Foreign investments also may be more susceptible to political, social, economic and regional factors than might be the case with U.S. securities.

Because the Fund's foreign investments will be, in part, in developing or "emerging market" countries, all the aforementioned factors are heightened and foreign investments risk is higher

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Benchmark Performance Risk — There is no guarantee or assurance that the methodology used to create the Benchmark will result in the Fund achieving high, or even positive, returns. The Benchmark may underperform more traditional indices. In turn, the Fund could lose value while the levels of other indices or measures of market performance increase. In addition, the Benchmark began publication on February 28, 2011 and accordingly the Benchmark has limited historical performance. The Benchmark does not in any way represent a managed hedge fund or group of hedge funds, and there is no guarantee that it will achieve returns correlated with any hedge fund, group of hedge funds, or the HFRI. Neither ProShare Advisors nor Merrill Lynch International have any control over the composition or compilation of the HFRI, and there is no guarantee that the HFRI will continue to be produced.

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Liquidity Risk — In certain circumstances, such as the disruption of the orderly markets for the securities or derivatives in which the Fund invests, the Fund might not be able to dispose of certain holdings quickly or at prices that represent true market value in the judgment of ProShare Advisors. Such a situation may prevent the Fund from limiting losses, realizing gains or achieving a high correlation with the Benchmark.

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Market Price Variance Risk — Fund Shares will be listed for trading on the NYSE Arca ("Exchange") and can be bought and sold in the secondary market at market prices. The market prices of Shares will fluctuate in response to changes in NAV and supply and demand for Shares. ProShare Advisors cannot predict whether Shares will trade above, below or at their NAV. Given the fact that Shares can be created and redeemed in Creation Units, ProShare Advisors believes that large discounts or premiums to the NAV of Shares should not be sustained. The Fund's investment results are measured based upon the daily NAV of the Fund. Investors purchasing and selling Shares in the secondary market may not experience investment results consistent with those experienced by those creating and redeeming directly with the Fund.

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Non-Diversification Risk — The Fund is classified as "non-diversified" under the 1940 Act, and has the ability to invest a relatively high percentage of its investments in the securities of a small number of issuers if ProShare Advisors determines that doing so is the most efficient means of meeting the Fund's objective. This makes the performance of the Fund more susceptible to a single economic, political or regulatory event than a diversified fund might be.

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Portfolio Turnover Risk — Active market trading of Shares may cause more frequent creation or redemption activities that could, in certain circumstances, increase the number of portfolio transactions. High levels of transactions increase brokerage costs and may result in increased taxable capital gains.

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Short Sale Exposure Risk — The Fund may seek short exposure through short sales or financial instruments such as swap agreements and future contracts consistent with its investment objective, which may cause the Fund to be exposed to certain risks associated with short exposure. These risks include, under certain market conditions, an increase in the volatility and decrease in the liquidity of the assets underlying the short position, which may lower the Fund's return or result in a loss. Short investment exposure may be considered an aggressive investment technique.

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Small- and Mid-Cap Company Investment Risk — The Benchmark, and by extension, the Fund, is exposed to stocks of small- and mid-cap companies. The risk of equity investing may be particularly acute for securities of issuers with smaller market capitalizations. Small- and mid-cap company stocks may trade at greater spreads or lower trading volumes and may be less liquid than the stocks of larger companies. Small- and mid-cap companies may have limited product lines or resources, may be dependent upon a particular market niche and may have greater fluctuations in price than the stocks of larger companies. Further, stocks of small- and mid-sized companies could be more difficult to liquidate during market downturns compared to larger, more widely traded companies. In addition, small- and mid-cap companies may lack the financial and personnel resources to handle economic or industry-wide setbacks and, as a result, such setbacks could have a greater effect on small- and mid-cap security prices.

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Debt Instrument Risk — The Fund may invest in, or seek exposure to debt instruments. Debt instruments may have varying levels of sensitivity to changes in interest rates, credit risk and other factors. Many types of debt instruments are subject to prepayment risk, which is the risk that the issuer of the security will repay principal prior to the maturity date. Debt instruments allowing prepayment may offer less potential for gains during a period of declining interest rates. In addition, changes in the credit quality of the issuer of a debt instrument can also affect the price of a debt instrument, as can an issuer's default on its payment obligations. Such factors may cause the value of an investment in the Fund to decrease. Also, the securities of certain U.S. government agencies, authorities or instrumentalities in which the Fund may invest are neither issued by nor guaranteed as to principal and interest by the U.S. government, and may be exposed to credit risk.

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Interest Rate Risk — Interest rate risk is the risk that debt securities or certain financial instruments may fluctuate in value due to changes in interest rates. Commonly, investments subject to interest rate risk will decrease in value when interest rates rise and increase in value when interest rates decline. The value of securities with longer maturities may fluctuate more in response to interest rate changes than securities with shorter maturities.

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Investment in Unregistered ETFs Risk — The Fund may invest in ETFs that are registered commodity pools, which are not registered under the 1940 Act and not subject to all of the investor protections of the 1940 Act.

Risk Lose Money [Text]

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You could lose money by investing in the Fund.

Risk Nondiversified Status [Text]

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Bar Chart and Performance Table [Heading]

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Investment Results

Performance Narrative [Text Block]

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Performance history will be available for the Fund after it has been in operation for a full calendar year.

Performance One Year or Less [Text]

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Performance history will be available for the Fund after it has been in operation for a full calendar year

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"Other Expenses" are based on estimated amounts for the current fiscal year.

[2]

ProShare Advisors LLC ("ProShare Advisors") has contractually agreed to waive Investment Advisory and Management Services Fees and to reimburse Other Expenses to the extent Total Annual Operating Expenses Before Fee Waivers and Expense Reimbursements, as a percentage of average daily net assets, exceed 0.95% through July 7, 2012. After such date, the expense limitation may be terminated or revised. Amounts waived or reimbursed in a particular contractual period may be recouped by ProShare Advisors within five years of the end of that contractual period to the extent that recoupment will not cause the Fund's expenses to exceed any expense limitation in place at that time. A waiver or reimbursement lowers the expense ratio and increases overall returns to investors.