This book analyzes examples of strategic engagement in order to identify the factors which contribute to the success or failure of defence diplomacy in preventing interstate conflict. For more than a century, nations have engaged in defence diplomacy to cultivate mutual understanding and mitigate conflict. A subset of defence diplomacy is strategic engagement, defined as peacetime defence diplomacy between nations that are actual or potential adversaries. This book analyzes three cases of strategic engagement in order to elucidate the factors which contribute to the success or failure of this diplomacy in preventing conflict. It uses an inductive framework to compare strategic engagement in the following cases: Anglo– German defence diplomacy prior to World War I; U.S.–Soviet defence diplomacy during the Cold War; and post-Cold War U.S.–China defence diplomacy. Based upon archival, literature, and personal interview research, the book argues that defence diplomacy can mitigate the risk of interstate conflict between potential adversaries. The lessons learned from this book can be employed to discern the significant elements conducive to achieving a successful outcome of strategic engagement and averting conflict or even war. This book will be of much interest to students of defence studies, diplomacy studies, foreign policy and international relations.