This chapter examines the price impact of large trades in futures markets across 14 stock index futures contracts in 11 different international markets. On the balance, we find that part of the initial price effect of futures trades is temporary. These initial price effects are partially reversed, implying that they incur a liquidity premium; though there is some variation in this finding across markets. We also find strong evidence that large buyer- and seller-initiated trades have positive and negative permanent effects on prices, implying they convey information. We conclude, similar to research based on equities markets, that traders in futures markets are informed.