This book provides an introduction to, and analysis of, the English School's views on International Relations as they developed from the somewhat vague state/society distinction to the present focus on foundation institutions, regional organisation and the globalization of international society. It focuses on key thinkers and texts and turning points and moves our understanding of the English School beyond the past work of the British Committee to the more recent work of Barry Buzan et. al. to offer a comprehensive overview and interrogation from the leading lights of this arm of International Relations thought. This volume is one of the cornerstones of the EISA sponsored Trends in European IR Theory series complementing the volumes on International Political Theory, Liberalism, Realism, International Political Economy, the post-positivist tradition, and Feminism published for the centenary of IR as a discipline.