For many decades, intersectoral action has been recognized as being of critical importance for the promotion and the protection of human health. In 1977, the World Health Assembly identified intersectoral action as an important component in achieving the goal of Health for All by the Year 2000; this has since been reemphasized by a number of international conferences. A major conference entitled "Intersectoral action for health: a cornerstone for health for all in the 21st century" was held in Canada in 1997. Described as "intersectoral action in motion", the conference assessed problems and progress, identifying future policy and strategies appropriate for the 21st century. The main conclusion of the meeting was that while intersectoral action is working, the successes and failures need to be further analysed, assessed and the lessons learned widely disseminated. Strategies need to be modified, adapted and implemented at global, national and subnational levels, in ways that are appropriate to different country situations and contexts. The full potential of intersectoral action for achieving health for all in the context of sustainable human development has yet to be realized.