The feasibility and effectiveness of a programme for the community control of rheumatic fever and rheumatic heart disease were studied in a cooperative multicentre project initiated and coordinated by the World Health Organization. The programme was carried out in seven centres in various developing countries of Africa, America, and Asia according to a common protocol, and is under way in a further eight countries in Latin America. Pilot community programmes were shown to be practicable and effective in reducing the burden of rheumatic heart disease in developing countries and their extension to cover entire populations should be encouraged.