This book provides practice-oriented insights into the agency of two previously underestimated actors in Southeast Asian regionalism: the ASEAN Secretariat and ASEAN’s dialog partners. In doing so, it offers an inside view of the policymaking processes in the ASEAN Political-Security and the ASEAN Economic Community, analyzing the interplay and agency by both actors in agenda setting, formulation, decision-making, implementation, and monitoring. Drawing on a trove of novel data, including never-before analyzed sources and numerous interviews with ASEAN insiders, the book showcases a number...