This book examines the development of a transnational private military and security contracting (PMSC) industry since 1945, an industry that has been both controversial and necessary to global security governance. The industry's trajectory is traced across a changing global state system and arenas of conflict - the Cold War, post Cold War, 'War on Terror,' inter and intrastate wars, and the convergence of war with crime and terrorism. The focus of this book is the PMSC industry operating from the liberal democracies of UK, USA and South Africa. The analytical framework is interdisciplinary, drawn from criminology, sociology and international relations, a unique approach in understanding the private military and security industry. The book explores how private entities operate within a security governance framework, facilitated by both strong and weak states. The mechanisms by which protection and risk management occur are explained by analogy to a mafia. As an industry in private protection, the mafia represents state function without accountability or legitimacy. The mafia analogy assists in identifying how the PMSC industry operates on behalf of strong states, offering protection for weak states.