Hedley Bull was one of the most important figures in the academic study of international relations. Although his work ranged widely, one simple but powerful idea constantly recurs: that sovereign states form among themselves a society and that this society must be understood on its own terms. The end of the Cold War and developments within international relations theory have once again thrown the social dimension of world politics into sharp relief. Although many have read Hedley Bull's The Anarchical Society, few are familiar with the breadth and range of his writing. This collection brings together Bull's most important work on international society, illustrating the richness and analytical rigour of his thought, and its evolution over time. The volume includes a comprehensive introduction which examines Bull's conception of international society, its relationship to contemporary theories of world politics, and its continued relevance to our understanding of the post-Cold War world.