This article studies whether and to what extent information affects the determination of spot exchange rates in an electronic limit-order foreign exchange market. Using the tick-bytick data of EUR-USD quotes and transactions on the Electronic Broking Services (EBS), the authors find evidence of intraweek and intraday variation in the level of information asymmetry. After macroeconomic announcements in the United States and Europe, the level of information asymmetry increases, which reveals that the informational role of order flow increases immediately after the release of macroeconomic announcements.