The Globalization of Security is an important rethinking of the connections between globalization and security, focusing on a conceptual examination of the role of the state combined with key case studies. The book provides an analysis of the changing nature of security issues through three interlinking ways of conceptualizing the globalization of security: the expansion of the scope of threat, thinking about security in 'global' terms, and the development of transnational networks of power. Three cases are examined to provide potential examples of the globalization of security: nuclear weapons and the globalization of threat, the globalization of the arms industry, and the global security aspects of migration and citizenship. The book provides a novel historical sociological approach to the globalization of security, advancing both the understanding of security and the theory of state power in international relations.