Historically, Greece's security has been closely tied to security in the Balkans. As a small country on its periphery, instability and unrest in the Balkans have had direct, and often significant, repercussions for Greece's own security, as the collapse of the former Yugoslavia dramatically demonstrated. As a result, Greece has been one of the leading proponents of increased regional cooperation in the area. The end of the Cold War and the collapse of Yugoslavia greatly complicated Greece's security dilemmas and forced Greece to forge a new Balkan policy. This chapter examines Greek security policy in the Balkans since the end of the Cold War. Greek-Turkish rivalry creates serious difficulties in Greece's relations with its Western allies. Unless Greece is able to find a way to resolve its differences with Turkey, security in the Balkans will remain a chimera and Greece's ability to play a stabilizing role in the region will remain impaired.