In this important study David Armstrong examines the impact of revolutionary states on the international system. These states have always posed major problems for the achievement of world order: revolution is often accompanied by international as well as civil conflict, while revolutionary doctrines have proven to be highly disruptive of the existing structure of international politics.;Dr Armstrong asks whether revolutionary states are 'socialized' into adopting acceptable patterns of international behaviour or whether it is international society that is forced to change when these new states appear.;He looks in detail at the French, American, and Russian revolutions and at several post-1945 revolutionary states; he also examines the relationship between revolutionary states and the principal ordering devices of international society: international law, diplomacy, and the balance of power. His book is a major contribution to international relations and an important development and application of the 'international society' concept.