The principal purpose of this thesis was to explain why the United States chose to implement, during the 1960’s, a balance of payments policy of the kind it had been committed to discouraging since the end of the Second World War. Capital controls were implicit in the norms of the Bretton Woods system as it had developed to the end of the 1960’s, but from the standpoint of U.S. foreign economic policy objectives, such controls could be justified only as a temporary expedient. It has been suggested that the reasons for the choice of capital controls by U.S. balance of payments policy-makers may be found in a complex interplay of both domestic and international political factors. What is especially salient in the evolution of the U.S. capital control program is that its sources and objectives changed during the decade of its operation. Starting as a primarily domestic bureaucratic policy response dictated by Treasury dominance of balance of payments policy, capital controls became part of a wider international strategy with its source more in the Executive branch of government than in bureaucratic policy preferences. The key to this shifting locus of authority is politicization: 268what began as a temporary balance of payments measure became part of a long struggle by the United States first to maintain the existing international monetary system, then to find a suitable stopgap measure while a new system was being negotiated, and finally, to force the principal allies of the United States to accept certain changes in the structure of the system.