After a long period of neglect, the social (or societal) dimension of the international system is being brought back into fashion within International Relations (IR) by the upsurge of interest in constructivism. For adherents of the English school, this dimension was never out of fashion, with the consequence that English school thinking itself has been somewhat on the margins of the discipline. In this book I will argue that English school theory has a lot to offer those interested in developing societal understandings of international systems, albeit itself being in need of substantial redevelopment.

International society is the flagship idea of the English school. It carves out a clearly bounded subject focused on the elements of society that states form among themselves. This domain has been quite extensively developed conceptually, and considerable work has also been done on the histories of international societies, particularly the creation of the modern international society in Europe and its expansion to the rest of the planet. World society also has a key place in English school theory, but is much less well worked out. While international society is focused on states, world society implies something that reaches well beyond the state towards more cosmopolitan images of how humankind is, or should be, organised. Quite what that ‘something’ that defines world society is, however, remains at best contested, and at worst simply unclear.