This document summarizes a study on the effects of currency futures trading on the volatility of the underlying Turkish currency market. The analysis uses a GARCH model and data from 1999-2011 on the returns of a currency basket consisting of the euro and USD. The results show that: 1) The introduction of currency futures reduces currency market volatility. 2) Considering the 2008 global crisis, currency futures trading yielded even more beneficial results by reducing volatility. 3) The onset of currency futures increased the efficiency of the spot currency market.