This book discusses preventive diplomacy as the next stage in the development of security cooperation in the Asia-Pacific region. The ASEAN Regional Forum (ARF) has identified the importance of this concept, although there has been limited progress in defining it. The book aims to deepen the understanding of the principles of preventive diplomacy. This collection includes works from key figures in the field, including Gareth Evans. Additionally, it features papers from Foreign Ministry officials and academics discussing the concepts and theories of preventive diplomacy. The book also presents relevant regional case studies, such as conflicts in the South China Sea and Moro. This project is a collaboration between the Strategic and Defence Studies Centre and the Institute of Defence and Strategic Studies in Singapore.