The South Carolina Department of Health and Environmental Control AIDS Program assessed the state population's knowledge and attitudes about AIDS and HIV transmission in 1987 and 1988. Each year approximately 1,800 adults were selected by a random 3-stage cluster design and asked seventeen questions by telephone about AIDS and HIV. Questions addressed attitudes, general knowledge, HIV transmission by casual contact, HIV transmission by sex and IV drug contact, and HIV transmission by blood donation and transfusion. Over 90 percent of respondents were knowledgeable about HIV transmission by high risk behaviors addressed in the questionnaire. Respondents were less knowledgeable about HIV transmission by casual contact (12 to 41 percent gave incorrect answers), HIV testing (45 to 48 percent gave incorrect answers), and transmission by blood donation (43 to 52 percent gave incorrect answers). In general, a higher percentage of correct responses were given in 1988 than in 1987. In regard to responses measured by this survey, we conclude that: (1) there is a high level of knowledge in the state about transmission by high risk behaviors, (2) there are still many misconceptions about casual transmission, HIV testing, and blood donation, and (3) there was improvement in knowledge about AIDS and HIV from 1987 to 1988.