According to the WTO, in July 2007 there were about 205 preferential trade agreements (PTAs) in force and by 2010 no fewer than 400 PTAs are expected to be implemented. This wave of PTAs, which started in the 1990s, is unprecedented both in terms of the number of countries and the breadth of issues they cover. Therefore it is imperative to get the basic facts about these agreements straight before we draw normative conclusions and make any detailed policy prescriptions. The paper by Horn, Mavroidis, and Sapir provides an excellent first step in this direction. The authors provide a careful and systematic classification of the policy areas covered by the reciprocal PTAs of the United States and European Union (EU) as well as the extent of their legal enforceability.

The areas are usefully divided into ones that are covered in some way in the WTO (WTO+) and those that are currently excluded from it (WTO-X). The main findings are the following. First, the obligations in WTO+ areas contained in these PTAs are often similar to the obligations in the WTO itself. Second, there are thirty-eight distinct WTO-X areas but only about eight appear to be legally enforceable. These are typically related to Intellectual Property, Investment, and Movement of Capital (both in U.S. and EU PTAs); Competition and Social Matters (EU); and Anti-Corruption, Environment, and Labor (U.S.).