During the 19th and 20th centuries, nationalism has posed a threat to international stability and the integrity of individual nation states. While the troubles in Northern Ireland have only slightly intruded on the world stage outside the British Isles, many of the issues raised are pertinent to international affairs, and, in particular, offer a laboratory for analysing ethnic conflict. The premiss of this book is that the Northern Ireland case offers an important testing ground for the management, suppression and voluntary cessation of ethnic violence.