The security environment and co-operation mechanisms in the Mediterranean have been changing since the end of the Cold War and, in parallel with these changes, the importance of the region has increased for the Western alliance. First, the number of security issues in the Mediterranean has increased. Second, the US, EU and NATO have redefined their Mediterranean policies and established new co-operation mechanisms in response to the changing security environment. In this context, the aim of this paper is to highlight the security and co-operation issues in the Mediterranean in the post-Cold War period and to discuss the European, American and NATO's policies towards the Mediterranean separately and in relation to each other. A third aim of this study is to evaluate Turkish foreign policy towards security and co-operation in the Mediterranean and the Turkish position vis-à-vis the European, American and NATO initiatives in the region. During the Cold War period, the Mediterranean was thought of in the context of the EastWest confrontation and the Middle East conflict. In the post-war years, the Soviet threat to Greece and Turkey, the US commitment to the security of Israel and increasing Soviet and Non-aligned influence among the Mediterranean Arab states in the 1960s, led to a permanent American military presence the Sixth Fleet and involvement in Mediterranean affairs. In this period, the Europeans except France were not willing or were unable to develop a European policy for the Mediterranean. Accordingly, the USA defined the strategic environment and the priorities for the Western alliance in the Mediterranean. However, Western strategic thinking was focused on the Central Front in the Cold War period and the Mediterranean remained secondary in importance and was considered as a strategic backwater for the Alliance