Prospectus by Investment Company - Form 497

BLACKROCK EUROFUND

(the "Fund")

Supplement dated November 21, 2024 to the Summary Prospectuses, the

Prospectuses and the Statement of Additional Information ("SAI") of the Fund, each dated October 28, 2024,

as supplemented to date

On November 19, 2024, the Board of Trustees (the "Board") of BlackRock EuroFund (the "Fund") approved certain changes relating to the Fund. In particular, the Board approved (i) a change in the name of the Fund to "BlackRock International Select Equity Fund", (ii) certain changes to the Fund's investment process and investment strategy, and (iii) the reduction of the Fund's expense cap on all share classes. In addition to these approvals, the Fund will also make a change to its benchmark index and a change in portfolio managers. These changes are expected to become effective on or about February 25, 2025.

Accordingly, effective on or about February 25, 2025, the following changes are made to the Fund's Summary Prospectuses, Prospectuses and SAI, as applicable:

Change in the Fund's Name

BlackRock EuroFund is renamed BlackRock International Select Equity Fund.

Change in the Fund's Benchmark Index

The Fund is replacing MSCI EMU Index as a performance benchmark against which the Fund measures its performance with MSCI EAFE Index.

Reduction of the Fund's Expense Caps on All Share Classes

The section of the Investor A, Investor C, Institutional and Class R Shares Summary Prospectus and Prospectus entitled "Key Facts About BlackRock EuroFund - Fees and Expenses of the Fund" or "Fund Overview - Key Facts About BlackRock EuroFund - Fees and Expenses of the Fund," as applicable, is deleted in its entirety and replaced with the following:

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund.You may payother fees, such as brokerage commissions and other fees to your financial professional or your selected securitiesdealer, broker, investment adviser, service provider or industry professional (including BlackRock Advisors, LLC("BlackRock") and its affiliates) (each, a"Financial Intermediary"), which are not reflected in the table andexample below.You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $25,000in the fund complex advised by BlackRock or its affiliates. More information about these and other discounts is available from your Financial Intermediary and in the "Details About the Share Classes" and the "Intermediary-Defined Sales Charge Waiver Policies" sections on pages 25 and A-1, respectively, of the Fund's prospectus and in the "Purchase of Shares" section on page II-93 of Part II of the Fund's Statement of Additional Information.

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:

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

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 rate 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, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 32% of the average value of its portfolio.

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The seventh and eighth paragraphs of the section of the Investor A, Investor C, Institutional and Class R Shares Prospectus entitled "Management of the Fund - BlackRock" are deleted in their entirety and replaced with the following:

With respect to the Fund, BlackRock has contractually agreed to waive and/or reimburse fees or expenses in order to limit Total Annual Fund Operating Expenses to the amounts noted in the table below.

The section of the Class K Shares Summary Prospectus and Prospectus entitled "Key Facts About BlackRock EuroFund - Fees and Expenses of the Fund" or "Fund Overview - Key Facts About BlackRock EuroFund - Fees and Expenses of the Fund," as applicable, is deleted in its entirety and replaced with the following:

Fees and Expenses of the Fund

This table describes the fees and expenses that you may pay if you buy, hold and sell Class K Shares of the Fund.Youmay pay other fees, such as brokerage commissions and other fees to your financial professional or your selectedsecurities dealer, broker, investment adviser, service provider or industry professional (including BlackRockAdvisors, LLC ("BlackRock") and its affiliates) (each, a"Financial Intermediary"), which are not reflected in thetable and example below.

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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:

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 rate 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, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 32% of the average value of its portfolio.

The seventh and eighth paragraphs of the section of the Class K Shares Prospectus entitled "Management of the Fund - BlackRock" are deleted in their entirety and replaced with the following:

With respect to the Fund, BlackRock has contractually agreed to waive and/or reimburse fees or expenses in order to limit Total Annual Fund Operating Expenses to the amount noted in the table below.

The fifth paragraph of the section entitled "Management, Advisory and Other Service Arrangements - Management Agreement" in Part I of the SAI is deleted in its entirety and replaced with the following:

Effective February 25, 2025, the Manager has contractually agreed to waive and/or reimburse fees or expenses in order to limit Total Annual Fund Operating Expenses After Fee Waivers and/or Expense Reimbursements (excluding Dividend Expense, Interest Expense, Acquired Fund Fees and Expenses and certain other Fund expenses (as defined in the Prospectuses)) as a percentage of average daily net assets to 1.10% for Investor A Shares, 1.85% for Investor C Shares, 0.85% for Institutional Shares, 1.35% for Class R Shares, and 0.80% for Class K Shares through June 30, 2026. This contractual agreement may be terminated upon 90 days' notice by a majority of the Independent Trustees or by a vote of a majority of the outstanding voting securities of the Fund.

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Changes in the Fund's Investment Strategy and Investment Process

The section of the Summary Prospectuses and Prospectuses entitled "Key Facts About BlackRock EuroFund - Investment Objective" or "Fund Overview - Key Facts About BlackRock EuroFund - Investment Objective," as applicable, is deleted in its entirety and replaced with the following:

The investment objective of BlackRock International Select Equity Fund (the "Fund") is to seek capital appreciation primarily through investment in equities of corporations domiciled in European countries. As an international fund, the Fund also invests in companies in other regions (generally in developed markets) around the world.

The section of the Summary Prospectuses and the Prospectuses entitled "Key Facts About BlackRock EuroFund - Principal Investment Strategies of the Fund," "Fund Overview - Key Facts About BlackRock EuroFund - Principal Investment Strategies of the Fund" or "Details About the Fund - How the Fund Invests - Principal Investment Strategies," as applicable, is deleted in its entirety and replaced with the following:

Under normal circumstances, the Fund will invest at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in equity securities of foreign issuers and derivatives that provide investment exposure to the securities included within that policy or to one or more market risk factors associated with such securities. The Fund's 80% policy is a non-fundamental policy of the Fund, and may not be changed without 60 days' prior notice to shareholders.

Equity securities include common stock, preferred stock, depositary receipts and securities or other instruments whose price is linked to the value of common stock. The Fund may also purchase convertible securities.

Foreign securities may include securities of (i) foreign government issuers, (ii) issuers organized or located outside the United States, (iii) issuers which primarily trade in a market located outside the United States, or (iv) issuers doing a substantial amount of business outside the United States, which the Fund considers to be companies that derive at least 50% of their revenue or profits from business outside the United States or have at least 50% of their sales or assets outside the United States. The Fund will allocate its assets among various regions and countries (but in no less than three different countries). The Fund will invest at least 65% of its net assets in equities of corporations domiciled in European countries. The Fund may invest in companies of any size.

The Fund may invest in both developed and emerging markets. In addition to investing in foreign securities, the Fund may manage its exposure to foreign currencies through the use of forward currency contracts and other currency derivatives. However, foreign exchange risk is not expected to be systematically hedged. From time to time, the Fund may own foreign cash equivalents or foreign bank deposits as part of the Fund's investment strategy. The Fund may also invest in non-U.S. currencies.

The Fund may use derivatives, including options, futures, swaps and forward contracts both to seek to increase the return of the Fund and to hedge (or protect) the value of its assets against adverse movements in currency exchange rates, interest rates and movements in the securities markets. In order to effectively manage cash flows into or out of the Fund, the Fund may buy and sell financial futures contracts or options on such contracts. Derivatives are financial instruments whose value is derived from another security, a commodity (such as oil or gas), a currency or an index.

While the Fund is classified as diversified under the Investment Company Act, it is generally expected to hold a limited number of issuers (25-45 holdings).

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The section of the Prospectuses entitled "Details About the Fund - How the Fund Invests - Investment Objective" is deleted in its entirety and replaced with the following:

The investment objective of the Fund is to seek capital appreciation primarily through investment in equities of corporations domiciled in European countries. This investment objective, as just stated, is a fundamental policy of the Fund and may not be changed without approval of a majority of the Fund's outstanding voting securities, as defined in the Investment Company Act of 1940, as amended (the "Investment Company Act"). As an international fund, the Fund also invests in companies in other regions (generally in developed markets) around the world.

The section of the Prospectuses entitled "Details About the Fund - How the Fund Invests - Investment Process" is deleted in its entirety and replaced with the following:

Investment decisions will be based on fundamental, company-specific research to identify and select equity and equity-related securities in a focused portfolio that, in the opinion of Fund management, have the potential to produce attractive long-term capital growth. Fund management research looks at a range of factors when selecting companies in which to invest including but not limited to an analysis of their competitive advantages, the impact of structural (such as economic, demographic or technological) changes, the quality of management teams and their financial discipline.

The section of the Prospectuses entitled "Details About the Fund - How the Fund Invests - Other Strategies" is amended to delete "Depositary Receipts", "Derivative Transactions", "Foreign Exchange Transactions", "Mid Cap Issuers" and "Small Cap Companies".

The section of the Summary Prospectuses and the Prospectuses entitled "Key Facts About BlackRock EuroFund - Principal Risks of Investing in the Fund" or "Fund Overview - Key Facts About BlackRock EuroFund - Principal Risks of Investing in the Fund," as applicable, are amended to add the following:

∎Depositary Receipts Risk - Depositary receipts are generally subject to the same risks as the foreign securities that they evidence or into which they may be converted. In addition to investment risks associated with the underlying issuer, depositary receipts expose the Fund to additional risks associated with the non-uniform terms that apply to depositary receipt programs, credit exposure to the depository bank and to the sponsors and other parties with whom the depository bank establishes the programs, currency risk and the risk of an illiquid market for depositary receipts. The issuers of unsponsored depositary receipts are not obligated to disclose information that is, in the United States, considered material. Therefore, there may be less information available regarding these issuers and there may not be a correlation between such information and the market value of the depositary receipts. While depositary receipts provide an alternative to directly purchasing underlying foreign securities in their respective markets and currencies, they continue to be subject to many of the risks associated with investing directly in foreign securities, including political, economic, and currency risk.

∎Derivatives Risk - The Fund's use of derivatives may increase its costs, reduce the Fund's returns and/or increase volatility. Derivatives involve significant risks, including:

Leverage Risk - The Fund's use of derivatives can magnify the Fund's gains and losses. Relatively small market movements may result in large changes in the value of a derivatives position and can result in losses that greatly exceed the amount originally invested.

Market Risk- Some derivatives are more sensitive to interest rate changes and market price fluctuations than other securities. The Fund could also suffer losses related to its derivatives positions as a result of unanticipated market movements, which losses are potentially unlimited. Finally, BlackRock may not be able to predict

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correctly the direction of securities prices, interest rates and other economic factors, which could cause the Fund's derivatives positions to lose value.

Counterparty Risk- Derivatives are also subject to counterparty risk, which is the risk that the other party in the transaction will be unable or unwilling to fulfill its contractual obligation, and the related risks of having concentrated exposure to such a counterparty.

Illiquidity Risk- The possible lack of a liquid secondary market for derivatives and the resulting inability of the Fund to sell or otherwise close a derivatives position could expose the Fund to losses and could make derivatives more difficult for the Fund to value accurately.

Operational Risk- The use of derivatives includes the risk of potential operational issues, including documentation issues, settlement issues, systems failures, inadequate controls and human error.

Legal Risk- The risk of insufficient documentation, insufficient capacity or authority of counterparty, or legality or enforceability of a contract.

Volatility and Correlation Risk- Volatility is defined as the characteristic of a security, an index or a market to fluctuate significantly in price within a short time period. A risk of the Fund's use of derivatives is that the fluctuations in their values may not correlate with the overall securities markets.

Valuation Risk - Valuation for derivatives may not be readily available in the market. Valuation may be more difficult in times of market turmoil since many investors and market makers may be reluctant to purchase complex instruments or quote prices for them.

Hedging Risk- Hedges are sometimes subject to imperfect matching between the derivative and the underlying security, and there can be no assurance that the Fund's hedging transactions will be effective. The use of hedging may result in certain adverse tax consequences.

Tax Risk - Certain aspects of the tax treatment of derivative instruments, including swap agreements and commodity-linked derivative instruments, are currently unclear and may be affected by changes in legislation, regulations or other legally binding authority. Such treatment may be less favorable than that given to a direct investment in an underlying asset and may adversely affect the timing, character and amount of income the Fund realizes from its investments.

∎Emerging Markets Risk- Emerging markets are riskier than more developed markets because they tend to develop unevenly and may never fully develop. Investments in emerging markets may be considered speculative. Emerging markets are more likely to experience hyperinflation and currency devaluations, which adversely affect returns to U.S. investors. In addition, many emerging securities markets have far lower trading volumes and less liquidity than developed markets.

∎Focus Risk- Under normal circumstances, the Fund focuses its investments in the securities of a limited number of issuers. This may subject the Fund to greater issuer-specific risk and potential losses than a fund that invests in the securities of a greater number of issuers.

The section of the Prospectuses entitled "Details About the Fund - Investment Risks - Principal Risks of Investing in the Fund" are amended to add the following:

∎ Depositary Receipts Risk - Depositary receipts are generally subject to the same risks as the foreign securities that they evidence or into which they may be converted. In addition to investment risks associated with the underlying issuer, depositary receipts expose the Fund to additional risks associated with the non-uniform terms that apply to depositary receipt programs, credit exposure to the depository bank and to the sponsors and other

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parties with whom the depository bank establishes the programs, currency risk and the risk of an illiquid market for depositary receipts. The issuers of unsponsored depositary receipts are not obligated to disclose information that is, in the United States, considered material. Therefore, there may be less information available regarding these issuers and there may not be a correlation between such information and the market value of the depositary receipts. While depositary receipts provide an alternative to directly purchasing underlying foreign securities in their respective markets and currencies, they continue to be subject to many of the risks associated with investing directly in foreign securities, including political, economic, and currency risk.

∎ Derivatives Risk - The Fund's use of derivatives may increase its costs, reduce the Fund's returns and/or increase volatility. Derivatives involve significant risks, including:

Leverage Risk - The Fund's use of derivatives can magnify the Fund's gains and losses. Relatively small market movements may result in large changes in the value of a derivatives position and can result in losses that greatly exceed the amount originally invested.

Market Risk- Some derivatives are more sensitive to interest rate changes and market price fluctuations than other securities. The Fund could also suffer losses related to its derivatives positions as a result of unanticipated market movements, which losses are potentially unlimited. Finally, BlackRock may not be able to predict correctly the direction of securities prices, interest rates and other economic factors, which could cause the Fund's derivatives positions to lose value.

Counterparty Risk- Derivatives are also subject to counterparty risk, which is the risk that the other party in the transaction will be unable or unwilling to fulfill its contractual obligation, and the related risks of having concentrated exposure to such a counterparty.

Illiquidity Risk-The possible lack of a liquid secondary market for derivatives and the resulting inability of the Fund to sell or otherwise close a derivatives position could expose the Fund to losses and could make derivatives more difficult for the Fund to value accurately.

Operational Risk- The use of derivatives includes the risk of potential operational issues, including documentation issues, settlement issues, systems failures, inadequate controls and human error.

Legal Risk- The risk of insufficient documentation, insufficient capacity or authority of counterparty, or legality or enforceability of a contract.

Volatility and Correlation Risk- The Fund's use of derivatives may reduce the Fund's returns and/or increase volatility. Volatility is defined as the characteristic of a security, an index or a market to fluctuate significantly in price within a short time period. A risk of the Fund's use of derivatives is that the fluctuations in their values may not correlate with the overall securities markets.

Valuation Risk- Valuation for derivatives may not be readily available in the market. Valuation may be more difficult in times of market turmoil since many investors and market makers may be reluctant to purchase complex instruments or quote prices for them. Derivatives may also expose the Fund to greater risk and increase its costs. Certain transactions in derivatives involve substantial leverage risk and may expose the Fund to potential losses that exceed the amount originally invested by the Fund.

Hedging Risk- When a derivative is used as a hedge against a position that the Fund holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. While hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying security, and there can be no assurance that the Fund's hedging transactions will be effective. The use of hedging may result in certain adverse tax consequences noted below.

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Tax Risk- The federal income tax treatment of a derivative may not be as favorable as a direct investment in an underlying asset and may adversely affect the timing, character and amount of income the Fund realizes from its investments. As a result, a larger portion of the Fund's distributions may be treated as ordinary income rather than capital gains. In addition, certain derivatives are subject to mark-to-market or straddle provisions of the Internal Revenue Code of 1986, as amended (the "Internal Revenue Code"). If such provisions are applicable, there could be an increase (or decrease) in the amount of taxable dividends paid by the Fund. In addition, the tax treatment of certain derivatives, such as swaps, is unsettled and may be subject to future legislation, regulation or administrative pronouncements issued by the Internal Revenue Service (the "IRS").

Regulatory Risk- Derivative contracts are subject to regulation under the Dodd-Frank Wall Street Reform and Consumer Protection Act (the "Dodd-Frank Act") in the United States and under comparable regimes in Europe, Asia and other non-U.S. jurisdictions. Under the Dodd-Frank Act, with respect to uncleared swaps, swap dealers are required to collect variation margin from the Fund and may be required by applicable regulations to collect initial margin from the Fund. Both initial and variation margin may be comprised of cash and/or securities, subject to applicable regulatory haircuts. Shares of investment companies (other than certain money market funds) may not be posted as collateral under applicable regulations. In addition, regulations adopted by global prudential regulators that are now in effect require certain bank-regulated counterparties and certain of their affiliates to include in certain financial contracts, including many derivatives contracts, terms that delay or restrict the rights of counterparties, such as the Fund, to terminate such contracts, foreclose upon collateral, exercise other default rights or restrict transfers of credit support in the event that the counterparty and/or its affiliates are subject to certain types of resolution or insolvency proceedings. The implementation of these requirements with respect to derivatives, as well as regulations under the Dodd-Frank Act regarding clearing, mandatory trading and margining of other derivatives, may increase the costs and risks to the Fund of trading in these instruments and, as a result, may affect returns to investors in the Fund.

Future regulatory developments may impact the Fund's ability to invest or remain invested in certain derivatives. Legislation or regulation may also change the way in which the Fund itself is regulated. BlackRock cannot predict the effects of any new governmental regulation that may be implemented on the ability of the Fund to use swaps or any other financial derivative product, and there can be no assurance that any new governmental regulation will not adversely affect the Fund's ability to achieve its investment objective.

Risks Specific to Certain Derivatives Used by the Fund

Swaps- Swap agreements, including total return swaps that may be referred to as contracts for difference, are two-party contracts entered into for periods ranging from a few days to more than one year. In a standard "swap" transaction, two parties agree to exchange the value(s) or cash flow(s) of one asset for another over a certain period of time. Swap agreements involve the risk that the party with whom the Fund has entered into the swap will default on its obligation to pay the Fund and the risk that the Fund will not be able to meet its obligations to pay the other party to the agreement. Swap agreements may also involve the risk that there is an imperfect correlation between the return on the Fund's obligation to its counterparty and the return on the referenced asset. In addition, swap agreements are subject to market and illiquidity risk, leverage risk and hedging risk.

Forward Foreign Currency Exchange Contracts- Forward foreign currency exchange transactions are OTC contracts to purchase or sell a specified amount of a specified currency or multinational currency unit at a price and future date set at the time of the contract. Forward foreign currency exchange contracts do not eliminate fluctuations in the value of non-U.S. securities but rather allow the Fund to establish a fixed rate of exchange for a future point in time. This strategy can have the effect of reducing returns and minimizing opportunities for gain.

Futures- Futures are standardized, exchange-traded contracts that obligate a purchaser to take delivery, and a seller to make delivery, of a specific amount of an asset at a specified future date at a specified price. The primary risks associated with the use of futures contracts and options are: (a) the imperfect correlation between the change in market value of the instruments held by the Fund and the price of the futures contract or option;

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(b) the possible lack of a liquid secondary market for a futures contract and the resulting inability to close a futures contract when desired; (c) losses caused by unanticipated market movements, which are potentially unlimited; (d) the investment adviser's inability to predict correctly the direction of securities prices, interest rates, currency exchange rates and other economic factors; and (e) the possibility that the counterparty will default in the performance of its obligations.

Options- An option is an agreement that, for a premium payment or fee, gives the option holder (the purchaser) the right but not the obligation to buy (a "call option") or sell (a "put option") the underlying asset (or settle for cash in an amount based on an underlying asset, rate, or index) at a specified price (the "exercise price") during a period of time or on a specified date. Investments in options are considered speculative. When the Fund purchases an option, it may lose the total premium paid for it if the price of the underlying security or other assets decreased, remained the same or failed to increase to a level at or beyond the exercise price (in the case of a call option) or increased, remained the same or failed to decrease to a level at or below the exercise price (in the case of a put option). If a put or call option purchased by the Fund were permitted to expire without being sold or exercised, its premium would represent a loss to the Fund. To the extent that the Fund writes or sells an option, if the decline or increase in the underlying asset is significantly below or above the exercise price of the written option, the Fund could experience a substantial loss.

∎ Emerging Markets Risk- The risks of foreign investments are usually much greater for emerging markets. Investments in emerging markets may be considered speculative. Emerging markets may include those in countries considered emerging or developing by the World Bank, the International Finance Corporation or the United Nations. Emerging markets are riskier than more developed markets because they tend to develop unevenly and may never fully develop. They are more likely to experience hyperinflation and currency devaluations, which adversely affect returns to U.S. investors. In addition, many emerging markets have far lower trading volumes and less liquidity than developed markets. Since these markets are often small, they may be more likely to suffer sharp and frequent price changes or long-term price depression because of adverse publicity, investor perceptions or the actions of a few large investors. In addition, traditional measures of investment value used in the United States, such as price to earnings ratios, may not apply to certain small markets. Also, there may be less publicly available information about issuers in emerging markets than would be available about issuers in more developed capital markets, and such issuers may not be subject to accounting, auditing and financial reporting standards and requirements comparable to those to which U.S. companies are subject.

Many emerging markets have histories of political instability and abrupt changes in policies. As a result, their governments are more likely to take actions that are hostile or detrimental to private enterprise or foreign investment than those of more developed countries, including expropriation of assets, confiscatory taxation, high rates of inflation or unfavorable diplomatic developments. In the past, governments of such nations have expropriated substantial amounts of private property, and most claims of the property owners have never been fully settled. There is no assurance that such expropriations will not reoccur. In such an event, it is possible that the Fund could lose the entire value of its investments in the affected market. Some countries have pervasive corruption and crime that may hinder investments. Certain emerging markets may also face other significant internal or external risks, including the risk of war, and ethnic, religious and racial conflicts. In addition, governments in many emerging market countries participate to a significant degree in their economies and securities markets, which may impair investment and economic growth. National policies that may limit the Fund's investment opportunities include restrictions on investment in issuers or industries deemed sensitive to national interests.

Emerging markets may also have differing legal systems and the existence or possible imposition of exchange controls, custodial restrictions or other foreign or U.S. governmental laws or restrictions applicable to such investments. Sometimes, they may lack or be in the relatively early development of legal structures governing private and foreign investments and private property. Many emerging markets do not have income tax treaties with the United States, and as a result, investments by the Fund may be subject to higher withholding taxes in

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such countries. In addition, some countries with emerging markets may impose differential capital gains taxes on foreign investors. Foreign companies with securities listed on U.S. exchanges may be delisted if they do not meet U.S. accounting standards and auditor oversight requirements, which may significantly decrease the liquidity and value of the securities.

Practices in relation to settlement of securities transactions in emerging markets involve higher risks than those in developed markets, in part because the Fund will need to use brokers and counterparties that are less well capitalized, and custody and registration of assets in some countries may be unreliable. The possibility of fraud, negligence, undue influence being exerted by the issuer or refusal to recognize ownership exists in some emerging markets, and, along with other factors, could result in ownership registration being completely lost. The Fund would absorb any loss resulting from such registration problems and may have no successful claim for compensation. In addition, communications between the United States and emerging market countries may be unreliable, increasing the risk of delayed settlements or losses of security certificates.

∎ Focus Risk- Under normal circumstances, the Fund focuses its investments in the securities of a limited number of issuers. This may subject the Fund to greater issuer-specific risk and potential losses than a fund that invests in the securities of a greater number of issuers.

The section of the Prospectuses entitled "Details About the Fund - Investment Risks - Other Risks of Investing in the Fund" are amended to delete "Depositary Receipts Risk", "Derivatives Risk", "Mid Cap Securities Risk" and "Small Cap and Emerging Growth Securities Risk".

Change in the Fund's Portfolio Managers

The section of the Summary Prospectuses and the Prospectuses entitled "Key Facts About BlackRock EuroFund - Portfolio Managers" or "Fund Overview - Key Facts About BlackRock EuroFund - Portfolio Managers," as applicable, is deleted in its entirety and replaced with the following:

Portfolio Managers

The section of the Prospectuses entitled "Details About the Fund - How the Fund Invests - About the Portfolio Management Team of the Fund" is deleted in its entirety and replaced with the following:

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The section of the Prospectuses entitled "Management of the Fund - Portfolio Manager Information" is deleted in its entirety and replaced with the following:

Portfolio Manager Information

Information regarding the portfolio managers of the Fund is set forth below. Further information regarding the portfolio managers, including other accounts managed, compensation, ownership of Fund shares, and possible conflicts of interest, is available in the Fund's SAI.

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Shareholders should retain this Supplement for future reference.

PR2SAI-EF-1124SUP

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