The Dictionary of International Security provides an easily understood introduction to the major concepts, issues, actors and institutions in the world of international security. Its 200 entries offer informed definitions of the subjects in question, as well as insights into the evolving debates over their meaning and importance. Entries are arranged alphabetically, from absolute war to weapons of mass destruction, and cover: types of security, such as national security and co-operative security; key concepts, including anarchy and balance of power; threats to security, from biological weapons to proliferation; responses to these threats, such as arms control and containment; terrorist organisations; topics related to peace and peacebuilding, such as conflict prevention and war termination; key international treaties and arms control initiatives; security and intelligence organisations; international organisations. Each entry is followed by carefully selected recommendations for additional reading to help students deepen their understanding of the topic. Overall, the dictionary is an invaluable resource for students, researchers and policy makers.