This book provides a brief, authoritative introduction to the history of security from Hobbes to the present day and a timely guide to contemporary security politics and dilemmas. It argues that the pursuit of security poses a significant challenge for criminal justice practices and values. It defends security as public good and suggests a framework of principles by which it might better be governed. Engaging with major academic debates in criminology, law, international relations, politics, and sociology, this book stands at the vanguard of interdisciplinary writing on security.