International labour migration is not a new issue, but it has become a key challenge in the twenty-first century as more barriers to trade in goods and services, including travel and communication, are coming down as a result of globalizing markets. And yet, labour markets remain the least exposed to the liberalization dynamics at the World Trade Organization (WTO) and in free trade agreements, making labour migration a topic at one of globalization’s key junctures, the one of markets versus rights, free movement versus border barriers, capital versus people, dignity versus exploitation. Several chapters in this volume (Chapter 2 by Cottier and Sieber-Gasser, Chapter 3 by Jacobsson, Chapter 13 by Naiki, and Chapter 20 by Amarelle and Fornalé) introduce the migration–trade nexus, which few publications have so far researched in necessary detail. International migration has recently been upgraded to a field of research and study in its own right – a recent series of research handbooks and textbooks testifies to this trend. All these volumes deal with the issue comprehensively in all its complexities (refugees, asylum, environmental and stranded migrants, internally displaced persons) and study it in its legal dimensions (right to leave, stay and return, repatriation, family reunification, free movement, temporary movement of natural persons in GATS Mode 4, post-admission human rights, etc.). The collection of chapters in this Handbook is different in the sense that it focuses exclusively on the international migrant worker and exposes the legal, political, economic, familial, and community ties she/he forges when moving back and forth across borders in search of new opportunities – and increasingly returning, even if temporarily, to the home community. This book aims to fill the lacunae in international labour migration studies, both for the beginner and more advanced seasoned scholar, for the legal practitioner and the economist, the sociologist and political scientist interested in the multiple fields of research an international labour migrant opens up when moving abroad for work.