This is the first book to apply the Clausewitzian Trinity of 'passion, chance, and reason' to the experience of real war. It explores the depth and validity of the concept against the conflicts of former Yugoslavia - wars thought to epitomise a post-Clausewitzian age. In doing so it demonstrates the timeless message of the Trinity, but also ties the Trinitarian idea back into Clausewitz's political argument.Intended to build on the existing corpus of scholarship, this book differs from the existing literature in two ways. By applying the Trinity to the wars of former Yugoslavia 1991-1995, it explores war at its micro-foundations, assessing the complex cause-and-effect nexus of reciprocity produced by actions between belligerents embroiled in dynamic competition perpetuated by their own interaction. Providing valuable insights into the complexities of real war fuelled by passion, undermined by chance, and shaped by reason, it is the first study to bridge the Clausewitzian world of theory with real experience. Examining each part of the triad separately, the book explores the multiple manifestations of hostility and chance, before then assessing the influence of these elements on the policies of the belligerents as the war evolved.