IWN seeks to replicate a benchmark which offers exposure small cap firms that exhibit value characteristics in the U.S. equity market. The investment thesis behind small caps is that these firms are likely to provide strong growth prospects to a portfolio and should have a much easier time growing then their large cap counterparts. However, these securities are extremely volatile and can experience large losses or gains in a very short period of time. Despite their volatility, these products should probably be in every investors' portfolio as they tend to move somewhat independently of large caps and can be a better 'pure play' on the American economy. This particular ETF, since it focuses on value securities, has certain biases in its portfolio holdings and may not offer as much of a cross section as funds such as IWM. However, IJS does an impressive job of dividing up assets as the fund holds close to 1,300 securities in total and doesn't give any one security more than 0.6% of the total assets. Thanks to this extreme level of diversification and IWN's reasonable expense ratio, the fund could make for a quality addition to portfolios of investors who are looking for small cap exposure but are seeking lower risk assets in the space. However, it should be noted that there are several other products in the space, namely VBR, VIOV, and VTWV, that offer similar diversification at a cheaper price, potentially making them better choices for long-term investors.