A questionnaire survey was held among 938 doctors and 2304 nurses to assess their attitudes toward AIDS and the influence of their concern about the occupational risks involved. The response was 65 and 72%, respectively. The results suggest that in treating patients with actual or possible HIV infection, in non-invasive procedures many doctors and nurses often take too many precautions, whereas in invasive procedures doctors often take too few. A minority of the respondents were in favour of testing all patients. The majority felt that patients in the high-risk groups should be tested. The percentage in favour of anonymous testing was considerably higher among the doctors than among the nurses. Most of the doctors and nurses were concerned about contagion by patients. This concern had a negative influence on their attitudes toward AIDS. Factual information alone does not suffice to dispel excessive concern. In training and educating medical personnel, attention should be devoted to cognitive as well as emotional aspects.