Despite the high frequency of their interactions, the policy coordination process between the United Nations (UN) and the Association of Southeast Asian Nations (ASEAN) has been underexamined in global and regional governance and ASEAN studies literature. To chart this important terrain, this incisive book contributes to scholarship by investigating UN-ASEAN policy coordination in the case of trafficking in persons (TIP). Guangyu Qiao-Franco advances a conceptual framework designed to explore the coordination between the UN and ASEAN, based on theories of policy transfer, norm diffusion, regime complex, and institutional interaction. By examining an extensive case study that traces developments in Southeast Asian regional governance since the early 1980s, this book contains rich information on the UN and ASEAN's TIP policies, lobbying and involvement of various actors, and the specific historical contexts of regional policy debates. Featuring analysis based on empirical data collected through 79 interviews with key participants in the TIP policy process across Southeast Asia, the book reveals the black box of ASEAN policymaking that has led to positive changes in human trafficking governance. This dynamic book will interest students and scholars of international relations, law, criminology, and migration studies. Its consideration of how disparate regional states might collaborate on human trafficking issues will further benefit practitioners and professionals working in governments of ASEAN member states, international organisations, and NGOs.