Fragmentation and coherence in international trade regulation are the core theme of this volume. For a long time, the General Agreement on Tariffs and Trade (GATT) led a life of its own in a self-contained regime. The evolution from tariff to non-tariff barriers brought about increasing overlaps with other regulatory areas, partly pertaining to core areas of domestic regulation. World Trade Organization (WTO) rules increasingly have an impact on other areas of law and policy, including environmental protection, agricultural and regional policies, labour standards, investment, human rights, culture and regional integration. Vice versa, other regulatory areas have an impact on trade rules. The process has resulted in tensions and challenges to the multilateral trading system with which the WTO has been confronted since its inception in 1995. Against this backdrop, this book offers an attempt to examine fragmentation in international trade regulation across a wide array of regulatory fields through the lens of a conceptually coherent theoretical framework. The effort to bring about greater coherence among different policy goals and fields, and thus to embed the multilateral trading system within the larger framework of international economics, law and international relations is the common thread connecting all chapters of this book and the proposals for reform which they submit.