This volume contains a collection of studies examining trade-related issues negotiated in regional trade agreements (RTAs) and how RTAs are related to the WTO's rules. While previous work has focused on subsets of RTAs, these studies are based on what is probably the largest dataset used to date, and highlight key issues that have been negotiated in all RTAs notified to the General Agreement on Tariffs and Trade (GATT) and the World Trade Organization (WTO). New rules within RTAs are compared to rules agreed upon by WTO members. The extent of their divergences and the potential implications for parties to RTAs, as well as for WTO members that are not parties to RTAs, are examined. This volume makes an important contribution to the current debate on the role of the WTO in regulating international trade and how WTO rules relate to new rules being developed by RTAs.