Do exchange rate regimes matter for the formation of countries’ external imbalances? Economists have thought so for over sixty years, and policymakers have made countless recommendations based on that presumption. But this had not been tested empirically until very recently, so it remained an opinion rather than a fact. In this post I show that having a flexible exchange rate regime leads to the correction of external imbalances in developing countries, offering some empirical support to a widely held belief. In contrast, this does not seem to be the case for advanced economies.