In 1969 the North Atlantic Treaty Organization (NATO) cstablishcd thc Committee on Challenges of Modern Society (CCMS). The subject of air pollution was from the thc very beginning one of the priority problems umier deliberation within the tJ-amcwork of various pi- lot studies undertaken by this committee. The organization of a yearly conference dealing with air pollution modelling and its application has become one of the main activities within thc pilot study rclating to air pollution. Pleasc see the listing on the next page for completed NATO/CCMS Pilot Studies and the International...