This Working Paper should not be reported as representing the views of the IMF.The views expressed in this Working Paper are those of the author(s) and do not necessarily represent those of the IMF or IMF policy. Working Papers describe research in progress by the author(s) and are published to elicit comments and to further debate.The paper examines factors affecting exchange rate volatility, with an emphasis on structural features of the foreign exchange regime. It draws for the first time on detailed survey data collected by the IMF on foreign exchange market organization and regulations. Key findings are that decentralized dealer markets, regulations on the use of domestic currency by nonresidents, acceptance of Article VIII obligations, and limits on banks' foreign exchange positions are associated with lower exchange rate volatility. The paper also provides support for earlier results on the influence of macroeconomic conditions and the choice of exchange rate regime on volatility. JEL Classification Numbers: F3, F31, F4