Recent experience has made clear the importance of macroeconomic stability, and exchange rate stability in particular, in generating support for regional integration. The tensions created by exchange-rate and financial volatility are clearly evident in the recent history of Mercosur and may also hinder the development of a Free Trade Area of the Americas. This essay argues that ambitious schemes for a single regional currency are not a practical response to this problem. Nor would a system of currency pegs or bands be sufficiently durable to provide a lasting solution. Instead, countries must solve this problem at home. In practice, this means adopting sound and stable monetary policies backed by a clear and coherent operating strategy, such as inflation targeting. With such policies in place, exchange rate volatility can be reduced to levels compatible with regional integration.