Can regional mechanisms better institutionalize the increasing complexity of economic and security ties among the countries in Northeast Asia? As the international state system undergoes dramatic changes in both security and economic relations in the wake of the end of the Cold War, the Asian financial crisis, and the attack of 9/11, this question is now at the forefront of the minds of both academics and policymakers. Still, little research has been done to integrate the analysis of security and economic analysis of changes in the region within a broader context that will give us theoretically-informed policy insights. Against this backdrop, this book investigates the origins and evolution of Northeast Asia's new institutional architecture in trade, finance, and security from both a theoretical and empirical perspective.