A comprehensive short-term campaign aimed of raising money to benefit a health charity organization also contained a considerable amount of information on prevention of heart disease. The campaign ended up with a six-hour TV-show broadcast by the only Norwegian TV channel covering the whole country. The 1987 fund-raising, which was extensively announced in TV and other media and involved large groups of the population, has been evaluated as a nationwide mass media-based health education campaign through a stratified random sample of 976 persons aged 15 years or more. 96% of the population were aware of the campaign, 72% had watched TV in addition to the news reports, 47% reported having acquired new knowledge and 22% reported having changed one or more habits as a result of the campaign. The factors most clearly associated with self-reported change of behaviour were a change of health behaviour by family/friends, new information and worry created by the campaign. The paper discusses the magnitude of the effects in relation to the weak design of the study, and elaborates upon the importance for impact on social environment, knowledge and arousal of fear for health behaviour.