This book questions the continued relevance of sovereignty to determine the nature of legal personality, the capacity to create international law, and the location of authority over territory. These issues are examined through the activities of non-state actors. At a time when many commentators are examining the role of non-state actors in terms of their obligations to guarantee human rights, this book focuses on their functions as promoters and protectors. In particular it examines how human rights standards are supervised by inter-governmental organisations, and how non-governmental organisations have played an instrumental role in the creation of human rights treaties. The book engages with the theoretical dimension of human rights law in a novel way by examining the nature and impact of human rights actors rather than human rights law itself on sovereignty. Rather than a strict sovereignty-centred positivist approach to international law it uses international relations literature as an aid to the analysis of non- state practice and proposes a fresh understanding of international law.