This new Handbook gathers together state-of-the-art theoretical reflection and empirical research by a group of leading international scholars in the subdiscipline of Critical Security Studies. In today's globalised setting, the challenge of maintaining security is no longer limited to the traditional foreign-policy and military tools of the nation-state, and security and insecurity are no longer considered as dependent only upon geopolitics and military strength, but rather are also seen to depend upon social, economic, environmental, ethical models of analysis and tools of action.