The Balkans have traditionally been an area of turmoil and political instability. The explosion of nationalism throughout the region and the intervention of the Great Powers in the 1800s earned the area the reputation as the powder keg of Europe. The onset of the Cold War dampened the most visceral conflicts in the area, and gave security relations in the Balkans a measure of stability and predictability. The Balkans were divided into blocs, with non-aligned Yugoslavia acting as a strategic buffer between East and West. Albania pursued a policy of splendid isolation, refusing to take part in any security arrangements or multilateral organizations in the region. The end of the Cold War has upset this delicate balance. Most notably, there has been an upsurge of nationalism and ethnic conflict throughout the region. This has been most visible in Yugoslavia, where old antagonisms between Croats and Serbs have resurfaced with a vengeance and contributed to the disintegration of the Yugoslavian federal state established after World War II. Conflict has not been limited to Yugoslavia, however. Anti-Hungarian demonstrations in Romania, the Turkish minority in Bulgaria, and tensions between Greece and Turkey over the treatment of the Turkish minority in Greece, have erupted as a result of this instability. The disintegration of Yugoslavia has unleashed powerful centrifugal forces that could intensify instability throughout the region. This article, reprinted from Survival, analyses the impact of recent political changes on security in the Balkans. It examines domestic developments, especially in revival of nationalism, the implications of the disintegration of Yugoslavia on regional security, the emergence of new political alignments in the areas, and the Greek-Turkish conflict. Finally it discusses the broader implications of the Yugoslav crisis for the emerging security architecture in Europe.