Humanitarian crises are a central problem of modern history and contemporary international relations. Since the 1990s, the aid sector has ballooned in size and is now a multi-billion-dollar industry. In this book, historian Julia F. Irwin traces the events and trends that defined modern humanitarianism, from the eighteenth century up to the present day. It describes the origins of international humanitarian action, the development of major humanitarian organizations and movements, the evolution of international humanitarian law, and the expansion of the international humanitarian sector. It examines organized efforts to save lives, alleviate suffering, and maintain human dignity amid major conflicts, disasters, refugee crises, and other humanitarian emergencies. At the same time, Irwin shows how beliefs about race, gender, religion, and nationality have historically influenced humanitarian sentiments and actions. Attuned to the distinctions between wartime, postwar, and non-conflict situations, Irwin assesses criticisms waged against humanitarian actions and debates over the legitimacy of humanitarian interventions. This Very Short Introduction also teases out the complex relationship between humanitarianism, human rights, and international development. Finally, this book surveys diverse and competing humanitarian traditions throughout the world.