What are the potential benefits from establishing international rules for the conduct of trade policy and how should these rules be designed? These questions are of central importance to the evolution of national trade policies in the post-war era, a period in which an elaborate system of international rules has evolved to facilitate the process of reciprocal trade liberalization. Yet the theory of trade policy has traditionally had little to say about these rules and the issues that underlie them. Below I review and synth~size several of the currents of a growing literature that is concerned with these questions. I attempt to accomplish three objectives: To describe the basic structure of international trade agreements as they exist in practice; to explore theoretically the normative consequences of actual and alternative trade agreements; and to offer some theoretically-based explanation for the structure of trade agreements that we observe. I attempt to achieve the first objective by describing the important features of the General Agreement on Tariffs and Trade. I attempt to achieve the latter two objectives by reviewing a body of literature and drawing out its implications as they relate to these issues.