iShares S&P Target Date 2020 Index Fund (the Fund) is an exchange-traded fund that seeks investment results that correspond generally to the price and yield performance of the S&P Target Date 2020 Index (the Index). The Fund seeks to achieve its objective by investing primarily in underlying funds that comprise its Index, as well as securities not included in its Index. The Fund invests at least 90% of its assets in securities of its Index. The Fund may invest in short-term instruments, including money market instruments. The Fund may also invest in various types of United States Government obligations. The Funds may invest in investment grade corporate bonds. The Fund’s investment advisor is BlackRock Fund Advisors.