The aim of the paper is to analyze the possibilities of overcoming the asymmetric shocks under fully fixed and fully floating exchange rate regimes, taking into consideration increasing financial integration which results in mounting capital flows. The analysis is based on the use of the Mundell-Fleming model within the framework of the theory of Optimum Currency Areas. The main conclusion is that (under the assumption that changes of nominal market interest rate are the only factor influencing the scale ant magnitude of capital flows) members of a currency union should offset negative results of the asymmetric shock with the use of instruments of fiscal policy. This appears to be more effective than monetary policy instruments. Hence, in analyzing the group of countries that want to establish a currency union or already have become members of such union, costs of the loss of monetary policy autonomy need not be related to benefits from preserving the autonomy. What should be taken into account is the quality of fiscal policy of these countries. Resignation from the autonomy of monetary policy would be a rash step only if the countries concerned are not prepared to conduct coordinated, disciplined and transparent fiscal policy.