During the last decade the issue of migration has increased in global prominence and has caused controversy among host countries around the world. To remedy the tendency of scholars to speak only to and from their own disciplinary perspective, this book brings together in a single volume essays dealing with central concepts and key theoretical issues in the study of international migration across the social sciences. Editors Caroline B. Brettell and James F. Hollifield have guided a thorough revision of this seminal text, with valuable insights from such fields as anthropology, demography, economics, geography, history, law, political science, and sociology. Each essay focuses on key concepts, questions, and theoretical frameworks on the topic of international migration in a particular discipline, but the volume as a whole teaches readers about similarities and differences across the boundaries between one academic field and the next. How, for example, do political scientists wrestle with the question of citizenship as compared with sociologists, and how different is this from the questions that anthropologists explore when they deal with ethnicity and identity? Are economic theories about ethnic enclaves similar to those of sociologists? What theories do historians the "essentializers" and demographers the "modelers" draw upon in their attempts to explain empirical phenomena in the study of immigration? What are the units of analysis in each of the disciplines and do these shape different questions and diverse models and theories? Scholars and students in migration studies will find this book a powerful theoretical guide and a text that brings them up to speed quickly on the important issues and the debates. All of the social science disciplines will find that this book offers a one-stop synthesis of contemporary thought on migration.