Why do countries differ substantially in the size of legal permanent immigration to the United States since 1965, even after the repeal of the discriminatory national origins quota system? The author demonstrates that development theory, world system theory and immigrants' social network theory all contain partial truths, but not one of them captures the entire immigration process. Here cross-national differences in the size of post-1965 immigration are shown as the outcomes of multi-dimensional forces, including the source country's development, U.S. involvement in the country, immigrants' resources, and the interactions of these factors. Scholars and readers interested in immigration, demography, sociology, history, international relations, cross-national analysis and social change will find this book an interesting and useful addition to their list of resources.