In this paper, the author deals with the transformation of NATOs role in the region of the Western Balkans in the last ten years. The1999 NATO Strategic Concept provided for a more active role of the Alliance in the consolidation of the security situation in Kosovo and Bosnia and Herzegovina. At the same time, the author points out NATOs New Strategic Concept and the perception of the role of Western Balkan and Southeast European states in this document. The author especially points to numerous segments of the gradual transformation of NATOs role, from being a factor that guarantees security in the region and influences the post-conflict consolidation and peace keeping, to the alliance that, due to the values it relies upon, keeps together most of the countries in the region, being an adequate framework for their international and security position.