Since 1985 the Swiss Federal Office of Public Health and the Swiss AIDS Foundation have been promoting AIDS prevention campaigns. A multi-media information campaign with the main slogan "STOP-AIDS" began in February 1987 and is still underway. Multiplying effects are stimulated. The evaluation of that strategy, based on 13 complementary studies, confirms its efficiency and feasibility. The evaluation process will continue in 1988. The campaign and its objectives reached the general population and the target groups. Noticeable changes in attitudes and behaviours are taking place in the way of better protection in various observed groups, moderately or strongly exposed to HIV infection. Condom sales have increased by nearly 60% in 1987 compared with 1986.