Investment Objective

Fees and Expenses

Annual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investments)

Example.

Expense Example	1 Year	3 Years
iSHARES ESG MSCI USA SMALL-CAP ETF \| iSHARES ESG MSCI USA SMALL-CAP ETF \| USD ($)	17	55

The Fund may pay 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 Fund shares are held in a taxable account. These costs, which are not reflected in the Annual Fund Operating Expenses or in the Example, affect the Fund’s performance.

The Fund seeks to track the investment results of the MSCI USA Small Cap Extended ESG Focus Index (the “Underlying Index”), which has been developed by MSCI Inc. (the “Index Provider” or “MSCI”). The Underlying Index is an optimized equity index designed to produce investment results comparable to the MSCI USA Small Cap Index (the “Parent Index”), while reflecting a higher allocation than that of the Parent Index to U.S. small-capitalization companies with favorable ESG profiles (as determined by MSCI). The Parent Index represents the bottom 14% of the U.S. equity market (as determined by MSCI).

In constructing the Underlying Index, the Index Provider begins with the Parent Index, excludes securities of companies involved in the business of tobacco, companies involved with controversial weapons, producers and retailers of civilian firearms, as well as companies involved in very severe business controversies (in each case as determined by the Index Provider), and then follows a quantitative process that is designed to determine optimal weights for securities in the Underlying Index to maximize exposure to companies with higher ESG ratings, subject to maintaining risk and return characteristics similar to those of the Parent Index.

For each industry, the Index Provider identifies key ESG issues that can lead to substantial costs or opportunities for companies (e.g., climate change, resource scarcity, demographic shifts). The Index Provider then rates each company’s exposure to each key issue based on the company’s business segment and geographic risk and analyzes the extent to which companies have developed robust strategies and programs to manage ESG risks and opportunities. The Index Provider scores companies based on both their risk exposure and risk management. To score well on a key issue, the Index Provider assesses management practices, management performance (through demonstrated track record and other quantitative performance indicators), governance structures, and/or implications in controversies, which all may be taken as a proxy for overall management quality. Controversies, including, among other things, issues involving anti-competitive practices, toxic emissions and waste, and health and safety, occurring within the last three years lead to a deduction from the overall management score on each issue. Using a sector-specific key issue weighting model, companies are rated and ranked in comparison to their industry peers. Key issues and weights are reviewed at the end of each calendar year. Corporate governance is always weighted and analyzed for all companies.

As of March 16, 2018, a significant portion of the Underlying Index is represented by securities of companies in the financials, industrials and information technology sectors. The components of the Underlying Index, and the degree to which these components represent certain industries or sectors, are likely to change over time.

BFA uses a “passive” or indexing approach to try to achieve the Fund’s investment objective. Unlike many investment companies, the Fund does not try to “beat” the index it tracks and does not seek temporary defensive positions when markets decline or appear overvalued.

Indexing may eliminate the chance that the Fund will substantially outperform the Underlying Index but also may reduce some of the risks of active management, such as poor security selection. Indexing seeks to achieve lower costs and better after-tax performance by keeping portfolio turnover low in comparison to actively managed investment companies.

BFA uses a representative sampling indexing strategy to manage the Fund. “Representative sampling” is an indexing strategy that involves investing in a representative sample of securities that collectively has an investment profile similar to that of an applicable underlying index. The securities selected are expected to have, in the aggregate, investment characteristics (based on factors such as market capitalization and industry weightings), fundamental characteristics (such as return variability and yield) and liquidity measures similar to those of an applicable underlying index. The Fund may or may not hold all of the securities in the Underlying Index.

The Fund generally will invest at least 90% of its assets in the component securities of the Underlying Index and may invest up to 10% of its assets in certain futures, options and swap contracts, cash and cash equivalents, including shares of money market funds advised by BFA or its affiliates, as well as in securities not included in the Underlying Index, but which BFA believes will help the Fund track the Underlying Index. The Fund seeks to track the investment results of the Underlying Index before fees and expenses of the Fund.

The Fund may lend securities representing up to one-third of the value of the Fund's total assets (including the value of any collateral received).

The Underlying Index and Parent Index are sponsored by MSCI, which is independent of the Fund and BFA. The Index Provider determines the composition and relative weightings of the securities in the Underlying Index and Parent Index and publishes information regarding the market value of the Underlying Index and Parent Index.

Industry Concentration Policy. The Fund will concentrate its investments (i.e., hold 25% or more of its total assets) in a particular industry or group of industries to approximately the same extent that the Underlying Index is concentrated. For purposes of this limitation, securities of the U.S. government (including its agencies and instrumentalities) and repurchase agreements collateralized by U.S. government securities are not considered to be issued by members of any industry.

As with any investment, you could lose all or part of your investment in the Fund, and the Fund's performance could trail that of other investments. The Fund is subject to certain risks, including the principal risks noted below, any of which may adversely affect the Fund's net asset value per share (“NAV”), trading price, yield, total return and ability to meet its investment objective.

Asset Class Risk. Securities and other assets in the Underlying Index or in the Fund's portfolio may underperform in comparison to the general financial markets, a particular financial market or other asset classes. Securities of companies that have positive or favorable ESG characteristics may underperform other securities.

Assets Under Management (AUM) Risk. From time to time, an Authorized Participant (as defined in the Creations and Redemptions section of this prospectus (the “Prospectus”)), a third-party investor, the Fund’s adviser or an affiliate of the Fund’s adviser, or a fund may invest in the Fund and hold its investment for a specific period of time in order to facilitate commencement of the Fund’s operations or to allow the Fund to achieve size or scale. There can be no assurance that any such entity would not redeem its investment or that the size of the Fund would be maintained at such levels, which could negatively impact the Fund.

Authorized Participant Concentration Risk. Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of institutions that may act as Authorized Participants on an agency basis (i.e., on behalf of other market participants). To the extent that Authorized Participants exit the business or are unable to proceed with creation or redemption orders with respect to the Fund and no other Authorized Participant is able to step forward to create or redeem Creation Units (as defined in the Purchase and Sale of Fund Shares section of the Prospectus), Fund shares may be more likely to trade at a premium or discount to NAV and possibly face trading halts or delisting.

Concentration Risk. The Fund may be susceptible to an increased risk of loss, including losses due to adverse events that affect the Fund’s investments more than the market as a whole, to the extent that the Fund's investments are concentrated in the securities of a particular issuer or issuers, country, group of countries, region, market, industry, group of industries, sector or asset class.

Cyber Security Risk. Failures or breaches of the electronic systems of the Fund, the Fund's adviser, distributor, and other service providers, market makers, Authorized Participants or the issuers of securities in which the Fund invests have the ability to cause disruptions and negatively impact the Fund’s business operations, potentially resulting in financial losses to the Fund and its shareholders. While the Fund has established business continuity plans and risk management systems seeking to address system breaches or failures, there are inherent limitations in such plans and systems. Furthermore, the Fund cannot control the cyber security plans and systems of the Fund’s service providers, the Index Provider, market makers, Authorized Participants or issuers of securities in which the Fund invests.

Equity Securities Risk. Equity securities are subject to changes in value, and their values may be more volatile than those of other asset classes. The Underlying Index is comprised of common stocks, which generally subject their holders to more risks than holders of preferred stocks and debt securities because common stockholders’ claims are subordinated to those of holders of preferred stock and debt securities upon the bankruptcy of the issuer.

ESG Investment Strategy Risk. The Fund’s ESG investment strategy limits the types and number of investment opportunities available to the Fund and, as a result, the Fund may underperform other funds that do not have an ESG focus. The Fund’s ESG investment strategy may result in the Fund investing in securities or industry sectors that underperform the market as a whole or underperform other funds screened for ESG standards. In addition, the Index Provider may be unsuccessful in creating an index composed of companies that exhibit positive or favorable ESG characteristics.

Financials Sector Risk. Performance of companies in the financials sector may be adversely impacted by many factors, including, among others, changes in government regulations, economic conditions, and interest rates, credit rating downgrades, and decreased liquidity in credit markets. The extent to which the Fund may invest in a company that engages in securities-related activities or banking is limited by applicable law. The impact of more stringent capital requirements and recent or future regulation of any individual financial company, or of the financials sector as a whole, cannot be predicted. In recent years, cyber attacks and technology malfunctions and failures have become increasingly frequent in this sector and have caused significant losses to companies in this sector, which may negatively impact the Fund.

Index-Related Risk. There is no guarantee that the Fund’s investment results will have a high degree of correlation to those of the Underlying Index or that the Fund will achieve its investment objective. Market disruptions and regulatory restrictions could have an adverse effect on the Fund’s ability to adjust its exposure to the required levels in order to track the Underlying Index. Errors in index data, index computations or the construction of the Underlying Index in accordance with its methodology may occur from time to time and may not be identified and corrected by the Index Provider for a period of time or at all, which may have an adverse impact on the Fund and its shareholders.

Industrials Sector Risk. Companies in the industrials sector may be adversely affected by changes in the supply of and demand for products and services, product obsolescence and changes in general economic conditions, among other factors. While the Fund seeks to invest in companies with positive or favorable environmental and social characteristics, companies in the industrials sector may also be adversely affected by claims for environmental damage or product liability.

Information Technology Sector Risk. Information technology companies face intense competition and potentially rapid product obsolescence. They are also heavily dependent on intellectual property rights and may be adversely affected by the loss or impairment of those rights.

Issuer Risk. The performance of the Fund depends on the performance of individual securities to which the Fund has exposure. Changes in the financial condition or credit rating of an issuer of those securities may cause the value of the securities to decline.

Management Risk. As the Fund may not fully replicate the Underlying Index, it is subject to the risk that BFA's investment strategy may not produce the intended results.

Market Risk. The Fund could lose money over short periods due to short-term market movements and over longer periods during more prolonged market downturns.

Market Trading Risk. The Fund faces numerous market trading risks, including the potential lack of an active market for Fund shares, losses from trading in secondary markets, periods of high volatility and disruptions in the creation/redemption process. ANY OF THESE FACTORS, AMONG OTHERS, MAY LEAD TO THE FUND'S SHARES TRADING AT A PREMIUM OR DISCOUNT TO NAV.

Non-Diversification Risk. The Fund may invest a large percentage of its assets in securities issued by or representing a small number of issuers. As a result, the Fund's performance may depend on the performance of a small number of issuers.

Operational Risk. The Fund is exposed to operational risks arising from a number of factors, including, but not limited to, human error, processing and communication errors, errors of the Fund’s service providers, counterparties or other third-parties, failed or inadequate processes and technology or systems failures. The Fund and BFA seek to reduce these operational risks through controls and procedures. However, these measures do not address every possible risk and may be inadequate to address significant operational risks.

Passive Investment Risk. The Fund is not actively managed, and BFA generally does not attempt to take defensive positions under any market conditions, including declining markets.

Risk of Investing in the United States. Certain changes in the U.S. economy, such as when the U.S. economy weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has exposure.

Securities Lending Risk. The Fund may engage in securities lending. Securities lending involves the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. These events could also trigger adverse tax consequences for the Fund.

Small-Capitalization Companies Risk. Compared to mid- and large-capitalization companies, small-capitalization companies may be less stable and more susceptible to adverse developments, and their securities may be more volatile and less liquid.

Tracking Error Risk. Tracking error is the divergence of a fund’s performance from that of the applicable underlying index. Tracking error may occur because of differences between the securities and other instruments held in a fund’s portfolio and those included in the applicable underlying index, pricing differences, differences in transaction costs, the fund’s holding of uninvested cash, differences in timing of the accrual of or the valuation of dividends or interest, tax gains or losses, changes to the applicable underlying index or the costs to the fund of complying with various new or existing regulatory requirements. This risk may be heightened during times of increased market volatility or other unusual market conditions. Tracking error also may result because a fund incurs fees and expenses, while the applicable underlying index does not.

As of the date of the Prospectus, the Fund has been in operation for less than one full calendar year and therefore does not report its performance information.