The UN and NATO have been jointly engaged in a range of conflicts in the post?Cold War era. Studies of these organizations, however, have largely overlooked the institutional interplay between their Secretaries-General. After brief reviews of the relationship between the UN and NATO and the leadership role that a Secretary-General can provide, this article examines the political relationship between Kofi Annan and Javier Solana across three stages of NATO?s 1999 Operation Allied Force in Kosovo. The findings show the important roles played and coordinated effort supplied by the Secretaries-General. This provides new perspectives on UN-NATO institutional coordination and has important implications for considering the relative security roles to be played by the UN and NATO in the future
