We study the macroeconomic effects of fiscal policies in an open economy. We emphasize two transmission mechanisms: the cost channel, by which wage government spending and labor taxes raise the real wage firms must pay, and the exchange rate channel, by which the nominal exchange rate shifts induced by fiscal policy have real effects if (some) prices and wage are sticky. The latter channel implies that changes in wage government spending or in labor taxation should have different effects under flexible than under fixed exchange rates. In a 1964-93 panel of OECD countries we find significant evidence for both channels. Moreover, we find that the real product wage and profitability are more responsive than quantities (employment and output) to fiscal policy innovations.