wars of aggression breaching international law? And finally: (III) Was the war which was presented to us as the paradigmatic example of a humanitarian-intervention-war, that is: the war in Kosovo in the spring of 1999 (with over 37,000 bombing missions), really justifiable as a humanitarian intervention? Many of us wanted to believe so at the time. Does our ex ante judgement hold today in an ex post reflection? And which lessons for the future should we learn from the success or failure of this humanitarian war? These are the questions proposed in this book; therefore, it is concerned with problems of semantics (part I), problems of moral assessment (part II) and with the moral, legal and political conclusions we draw from our experiences with the war in Kosovo, our primary example of a humanitarian intervention (part III). International experts in the areas of philosophy, international law, sociology and peace studies debated these questions vigorously for several days. This is the resulting volume.