Long-only commodity index funds have been blamed by other futures market participants for inflating commodity prices, increasing market volatility, and distorting historical price relationships. Much of this criticism is leveled without any formal empirical support or even cursory data analyses. The Commodity Futures Trading Commission makes available the positions held by index funds and other large traders in their Commitment’s of Traders report. In this research, we make an initial assessment of the size and activity of index funds in traditional agricultural futures markets. The results suggest that after an initial surge from early 2004 through mid-2005, index fund positions have stabilized as a percent of total open interest. Speculative measures—such as Working’s T—suggest that long-only funds may provide a benefit in markets traditionally dominated by short hedging.