As we celebrate the 40th Anniversary of the ASEAN-Japan Dialogue Partnership, the essays in this book remind us, and amplify the ASEAN-Japan relations. The complexities of this relationship, including the external influences which have impinged on its development over the years, are cogently discussed and recorded for the younger generation and students of ASEAN-Japan ties. The intricacy and spread of ASEAN-Japan cooperation mechanisms are also well highlighted in this book, while several thought-provoking commentaries on the future of this four-decade old partnership give pause to the readers. Many of the challenges that exist in this relationship originated from domestic political dynamics in the ASEAN countries and Japan, as well as from the neighbouring states and key trading partners.