Asian regional integration has shown remarkable progress since the end of the 1990s, but is currently at a major crossroads amid confusion of debate over the direction and effectiveness of integration, and friction brought about by the "rise of China". Meanwhile, the changing balance of power among nations, the rise of non-state actors, the "internationalization of internal problems" and the "internalization of international problems", are rendering the cross-national structure of Asia increasingly complex and multilayered. Signs of instability of the global economy are growing and environmental and resource challenges are deepening. The Asian region needs new approaches to understanding the state of regional integration and mechanisms to address the challenges. Regional Integration in East Asia: Theoretical and Historical Perspectives is the culmination of five years of intensive research on Asian regional integration by Waseda University. It re-examines theoretical approaches to comprehending the actual state of integration in the region and presents the most compelling among them. It also examines the state of regional cooperation in Asia in areas ranging from the economy to energy and the environment, security and education. In addition, the book offers long-term historical perspectives, including especially those of Japan, ASEAN and China, on Asian regional integration. Thus, it sheds light on diverse aspects, levels of analysis and time spans, and offers a comprehensive portrayal of the actual condition of Asia and the state of endeavours to build regional cooperation and institutions. This volume will open a new research frontier in Asian regional integration research.