The book provides a comprehensive and critical analysis of the theoretical and empirical literature in international economics arising from the proliferation of regional integration schemes in the last four decades. The focus is on the pure theoretical and empirical work in the field, covering all recent developments in theoretical work and measurement techniques in regional integration. The new book fully updates the analysis in the author's very well received The Theory and Measurement of International Economic Integration (1989) to take into account the impact of a further decade of rapid integration around the world. Detailed empirical analysis of the major integration schemes themselves can be found in the author's collection International Economic Integration (1997).