Surveillance, it is often said, is the International Monetary Fund’s most important responsibility. But, what is IMF surveillance? What does it seek to achieve? What does it actually accomplish, for good or ill? Conceptually, the IMF’s responsibilities for surveillance derive from its original role as the overseer of the Bretton Woods system of fixed-but-adjustable exchange-rate parities. That system collapsed in the early 1970’s. But, views of skeptics notwithstanding, the IMF has survived. Indeed, the membership has consistently reaffirmed the value it sees in the IMF by, among other things, periodically authorizing substantial increases in the Fund’s resources.