"A great deal of post-war trade liberalization resulted from regional, preferential trade agreements. Preferential trade agreements cut tariffs on goods originating only in those nations that have signed the agreement. Therefore, they need 'rules of origin' to determine which goods benefit from the tariff cut. Rules of origin have long been ignored for two good reasons: they are dauntingly complex and at first sight appear mind-numbingly dull. The third standard reason for ignoring them - the assertion that they do not matter much - turns out to be wrong. We show that rules of origin are important barriers to trade. Moreover, such rules are emerging as an important trade issue for three additional reasons. First, preferential trade deals are proliferating worldwide. Second, the global fragmentation of production implies complex international supply chains which are particularly constrained and distorted by rules of origin. Third, the extent to which regionalism challenges the WTO-based trading system depends in part on incompatibilities and rigidities built into rules of origin." Copyright � CEPR, CES, MSH, 2005.

"The reduction in trade barriers in Europe through the Single Market Programme (SMP) was intended to increase competition in European markets, and hence welfare and efficiency. The paper examines how the SMP has affected trade patterns and what can be learnt from this regarding the impact on competitive behaviour. Combining an econometric and computable general equilibrium methodology, it is argued that (1) the SMP has indeed had a strong impact on competitive behaviour; (2) the extent of the impact depends both on changes in the intensity of competition as well as on changes in the nature of competitive interaction; (3) while all economies experience potentially large welfare gains from the SMP, it is the smaller economies that experience the larger gains, but this in turn suggests that they experience a greater degree of restructuring." Copyright Centre for Economic Policy Research, Centre for Economic Studies, Maison des Sciences de l'Homme 1997.