Since World War II, a fundamental objective of the foreign policy of the United States has been to strengthen political and economic relationships among free-world nations. An integral element of this policy has been the expansion of international trade on mutually beneficial terms. The legal and practical problems of reducing or eliminating restrictions on the international movement of commodities have therefore assumed a major importance.

International commodity transactions have traditionally been subject to a wide range of such restrictions. In the case of imports, the most familiar barriers are tariffs and formal quotas or embargoes imposed by national governments. In recent years, however, the major industrialized nations have tended toward a gradual reduction in tariff levels. Concurrently with this trend, and partially in consequence of it, there has developed an increasing awareness that other forms of import restrictions may constitute equal or even greater obstacles to trade.