This book addresses questions arising from the development and use by rulers and states of military, diplomatic, economic and political intelligence from ancient times to the present day. Intelligence has become a recognized element in international discourse in the post-Cold War era, because of perceived new threats such as Islamic and other terrorisms, and WMD proliferation, which have prompted moves towards far greater interstate and transnational intelligence cooperation, and because of the growth in a culture of accountability in western societies which has seen the gradual release of historical records long kept secret for national security reasons. These cast fresh light on the extent and impact of secret intelligence on policy making and decision taking, in peace as well as war. The contributions in this book take a long view of intelligence as an element in state and international affairs, and explore not only the more cerebral aspects of the question - broadly speaking, the collection, assessment and use of information - but more questionable aspects of broader intelligence related activities, such as the circulation of disinformation, destabilization of states and movements, assassinations, and covert warfare against states, movements and peoples.