Résumé : The disclosure of information about the policy making process and the release of new databases may add relevant information about the exchange rate to guide the public's expectation, but may also mislead it. Asymmetric information also reinforces the importance of the learning process for policy makers and financial markets. This dissertation focuses on the role of information in the political economics of exchange rates. The two first chapters provide empirical studies of how access to information shapes and constraints the choice of exchange rate policy (official statement and implemented policy). The last chapter considers the question of whether international banks learn from their previous crisis experiences and reduce their lending to developing countries as a result of a financial crisis. It focuses on the experience accumulated with past financial crises.