This project aims to examine the transformation of the security doctrine of NATO after the Cold War and its effects on the intervention in the Republic of Macedonia. The disintegration of the Soviet Block meant a change in the definition of threats against the survival of members of the Atlantic Alliance. Since the nineties, interethnic natured conflicts became part of the risks that transgress security of Allies and the stability of the Euro-Atlantic area. Therefore, NATO intervened in those States in which ethnic armed confrontations prevailed, as was the case of Macedonia. There, the Atlantic Alliance executed a series of crisis management operations to counter the threat. The phenomenon to be studied in this research paper will be analyzed through Subaltern Realism and the Theory of Collective Security.
