For many years, Greece and Turkey have been involved in aggressive rivalry over Cyprus and large areas of the Aegean Sea. Their conflicts endanger the peace between these two NATO allies and have even brought the two nations to the brink of war, but no agreement has been reached despite their mutual assistance in the aftermath of the earthquakes suffered by both countries in the summer of 1999. This work provides an in-depth discussion of how the conflicts began, the matter of Cyprus and international law, disputes and near-war situations over the Aegean, the dynamics of and prospects for a new Greek-Turkish partnership and current developments in disputes and relations.