Traditionally, the study of regionalism in international political and economic relations has been confined predominantly to the highly institutionalized forms of international cooperation among countries in the industrialized world. In the introductory chapter to this book, it was argued that recent changes in the international political economy have increased the importance of new forms of regionalism—most notably those involving developing (peripheral and semi-peripheral) countries, on the one hand, and a mix of developing and industrialized countries, on the other.