This report describes a contact investigation conducted in rural South Carolina to identify, counsel, and educate persons infected with or exposed to the human immunodeficiency virus (HIV). Starting with one HIV antibody—positive man and his 19 sex contacts, we identified 83 sex contacts of HIV antibody—positive men. Of these, 64 were residents of the county and 63 (98%) agreed to be tested for evidence of HIV infection. Eight (13%) were HIV antibody positive. Thirty-six initially HIV antibody—negative men were reevaluated at a six-month follow-up visit, and three had seroconverted during this time. Of 25 men who reported practicing anal receptive intercourse, 13 (52%) were HIV antibody positive vs none of 43 men who reported strictly anal insertive intercourse. Comparing reported numbers of sexual contacts for the six-month periods before and after our initial investigation, the mean numbers of named sex contacts decreased by 82% for antibody-positive men and 54% for antibody-negative men. None of the men reported using condoms before entering the study; at the six-month follow-up visit, four (80%) of five of the antibody-positive men and 25 (69%) of 36 of the antibody-negative men reported using condoms at least some of the time.