Regional integration schemes have multiplied in the past few years and the importance of regional groups in trade, money and politics is increasing dramatically. 1 Regional integration, however, is no new phenomenon. Examples of Staatenbünde, Bundesstaaten, Eidgenossenschafiten, leagues, commonwealths, unions, associations, pacts, confederacies, councils and their like are spread throughout history. Many were established for defensive purposes, and not all of them were based on voluntary assent. This article looks at a particular set of regional integration schemes. The analysis covers cases that involve the voluntary linking in the economic and political domains of two or more formerly independent states to the extent that authority over key areas of national policy is shifted towards the supranational level.