This book is about international humanitarian law or - as it is also called - the law of armed conflict""or ""law of war"". It emerged from a series of lectures delivered at the Hague Academy of International Law. The author deals with war and the means by which international law attempts to contain and, as it were, ""humanize"" organized violence. But the ambitions of the author go beyond the battlefield. The book explores the many complex ways in which law functions to regulate warfare, in theory and practice. The author looks into treaties and other sources of international law, but he also tries to step outside the boundaries of ""black-letter law""to deal broadly with such matters as the influence of culture in shaping the norms on war, the institutions that develop those norms and work for their universal acceptance, the networks of humanitarian actors in this area and the legal procedures in which the law of war and its various institutions are embedded. The book demonstrates that even wars are, in various ways, conducted in ""the shadow of the law"".