Book excerpt: The nature and scope of UN Security Council decisions - significantly changed in the post-Cold War era - have enormous implications for the conduct of foreign policy. The UN Security Council offers a comprehensive view of the council both internally and as a key player in world politics. Focusing on the evolution of the council's treatment of key issues, the authors discuss new concerns that must be accommodated in the decisionmaking process, the challenges of enforcement, and shifting personal and institutional factors. Case studies complement the rich thematic chapters. The book sheds much-needed light on the central events and trends of the past decade and their critical importance for the future role of the council and the UN in the sphere of international security.