This book shows how changing diplomatic practices are central in explaining key dimensions of world politics, from law to war.Diplomacy can help explain key dimensions of world politics, including international law, war, international organizations, humanitarianism, and economic governance. Examining contemporary changes in diplomacy through social theoretical frameworks, this book sheds new light on how the evolution of diplomacy is integral to the making and remaking of world politics.Diplomacy can help explain key dimensions of world politics, including international law, war, international organizations, humanitarianism, and economic governance. Examining contemporary changes in diplomacy through social theoretical frameworks, this book sheds new light on how the evolution of diplomacy is integral to the making and remaking of world politics.This book examines world politics through the lens of diplomatic practice. It argues that many global phenomena of our time, from the making of international law to the constitution of international public power, through humanitarianism and the maintenance of global hierarchies, are made possible and shaped by evolving forms of diplomacy. The study of diplomacy is largely dominated by firsthand accounts and historical treaties, with little effort at theoretical discussion. This book shows how diplomatic studies can benefit from more explicit theorizing, and argues that the study of world politics should pay more attention to what goes on in the diplomatic 'engine room' of international politics.Introduction Ole Jacob Sending, Vincent Pouliot and Iver B. Neumann; Part I. Making of International Institutions: 1. International law and the politics of diplomacy Ian Hurd; 2. Diplomacy, war, and world politics Tarak Barkawi; 3. The practice of permanent representation to international organizations Vincent Pouliot; Part II. Making International Cooperation: 4. From representation to governing: diplomacy and the constitution of intlãf