Accidents are unexpected events usually producing injury. Many victims of trauma have a history of recurrent accidents. This study is a preliminary effort to verify the hypothesis that accidents may be considered as a recurrent disease in certain families; these children and families belong to a 'high risk group'. Two-hundred seventy-nine high school pupils participated in the study. Every pupil had experienced 1.7(+/- 1.7) mild to serious injuries that necessitated medical treatment during the years of elementary and high school. The geographical location of accidents was as follows: 26.4% were on the road; 23.1% occurred at school; 28.6% were associated with sport activities; and 22% occurred at home. The prevalence of injuries among boys was higher than among girls. A correlation was found between the number of accidents of the pupils and those of close family members, suggesting that these children and families are prone to accidents and form a 'high risk group'. The knowledge of accident and injury prevention did not change significantly during high school studies. The principal source of knowledge of accident and injury prevention of the pupils were the media: TV (98.8%), newspapers: (65.6%), and radio (58.1%). The contribution of physicians and nurses to this knowledge was very slight (16.5%). These families should be a target population; an educational program should be organized and transmitted by the media; family meetings with educational advisors, physicians and nurses should take place at school, especially for these target families. As a preventive measure for all, and especially to the high risk group, we would suggest that high school pupils work for 1-3 months in rehabilitation centers in which they can see the consequences of accidents and thereby gain an understanding of the effects of injury on the patient and his family.