Agricultural trade barriers and producer subsidies inflict real costs, both on the countries that use these policies and on their trade partners. This report quantifies the costs of global agricultural distortions and the potential benefits of their full elimination. The report concludes that eliminating global agricultural policy distortions would result in an annual world welfare gain of $56 billion. The report also analyzes the effects on U.S. and world agriculture if only partial reform is achieved in liberalizing tariffs, tariff-rate quotas (limits on imported goods), domestic support, and export subsidies.