Privacy is one of the most contested concepts of our time. This book sets out a rigorous and comprehensive framework for understanding debates about privacy and our rights to it. Much of the conflict around privacy comes from a failure to recognise divergent perspectives. Some people argue about human rights, some about social conventions, others about individual preferences and still others about information and data processing. As a result, 'privacy' has become the focus of competing definitions, leading some to denounce the 'disarray' in the field. But as this book shows, disagreements about the role and value of privacy obscure a large amount of agreement on the topic. Privacy is not a technical term of law, cybersecurity or sociology, but a word in common use that adequately expresses a few simple and related ideas.