This book analyses UK defence as a complex, interdependent public-private enterprise covering politics, management, society, and technology, as well as the military.Building upon wide-ranging applied research, with extensive access to ministers, policy makers, senior military commanders, and industrialists, the book characterises British defence as a phenomenon that has endured extensive transformation this century. Looking at the subject afresh as a complex, extended enterprise involving politics, alliances, businesses, skills, economics, military practices, and citizens, the authors profoundly reshape our understanding of ‘defence’ and how it is to be commissioned and delivered in a world dominated by geopolitical risks and uncertainties. The book makes the case that this new understanding of defence must inevitably lead to new policies and processes to ensure its health and vitality.This book will be of much interest to students of defence studies, British politics, and military and strategic studies, as well as policy makers and practitioners.