This study grew out of an interest in the process of economic adjustment among regions of a large common-market area such as the European Economic Community. The chief purpose of the study is to describe Puerto Rico's balance of payments experience and to analyze that experience using international trade analogies. A UNC Press Enduring Edition -- UNC Press Enduring Editions use the latest in digital technology to make available again books from our distinguished backlist that were previously out of print. These editions are published unaltered from the original, and are presented in affordable paperback formats, bringing readers both historical and cultural value.