Security Studies traces its origins to work on the causes of war. It remains the most significant subdiscipline of International Relations and, at the beginning of the twenty-first century, its concerns with the security of the international system and the individual, as well as the state, remain as pertinent and urgent as ever. While-especially since the events of 11 September 2001 and the remilitarization of US foreign policy-the focus on states and military power remains central to Security Studies, the subject also embraces economic, societal, and environmental security. Furthermore, Security Studies has spawned a dizzying range of competing theoretical approaches-liberal, constructivist, critical, postmodernist, and feminist among them-to challenge the dominant 'realist' take on security.

Addressing the need for an authoritative reference work to make sense of this rapidly growing and ever more complex corpus of scholarly literature, Security Studies is a new title in the Routledge series, Critical Concepts in International Relations. Edited by Theo Farrell of King's College London and chair of the International Security Studies section of the International Studies Association, it is a five-volume collection of the foundational and the very best cutting-edge scholarship.

Security Studies is fully indexed and includes a comprehensive introduction, newly written by the editor, which places the collected material in its historical and intellectual context. It is an essential reference work and is destined to be valued by scholars and students-as well as policy-makers and practitioners-as a vital one-stop research and pedagogic resource.