Investors have many options to invest in mutual funds and exchange-traded funds that passively track the performance of the Russell 2000 index. The most heavily traded of the ETFs is the iShares Russell 2000 index ETF (NYSEARCA:IWM).
Funds such as the RVX Emerging Markets Equity Opportunity Fund are ideal for investors who want exposure to a specific market. This fund is an offshoot of the Russell 2000. Another example is the Vanguard Russell 2000 ETF (NASDAQ:VTWO). This fund invests in all 2,000 stocks according to their relative weights. This fund's low (0.10%) expense ratio is an attractive feature.
Investors who are specifically interested in trading the index based on the reconstitution can trade the CME E-mini Russell 2000 Index (RTY) Future contracts.  Doing so means the futures contracts will track the index, and the investor does not have to be concerned about any tracking errors caused by the reconstitution.