Correctional department medical directors in all 50 States and appropriate corrections administrators in Washington, D.C.; Puerto Rico; the Virgin Islands; and Guam were surveyed. Twenty-six written surveys were returned, with 22 followup calls yielding more information. There were 420 diagnosed AIDS cases in prisons, with 85 percent in New York, New Jersey, and Florida. An estimated half of those have died. The survey indicated that blacks, Hispanics, and intravenous drug users are heavily represented among prisoners with AIDS and AIDS Related Complex (ARC). Sixteen States had intake services to identity those at high risk for AIDS or those with ARC. No State relied solely on the HTLV-III antibody test, although 60 percent of respondents used it in some fashion. Despite reported problems with the test, prisoners and correctional facilities were demanding its increased use because they mistakenly assumed it diagnosed AIDS. Forty-eight percent of respondents segregated inmates with confirmed AIDS diagnoses, 17 percent were developing a segregation policy, and 5 percent decided segregation on an individual basis. Although most prisons segregated as protection against infection and other inmates, Cordero v. Coughlin stipulated that segregation must provide more than 24-hour isolation cells. Prisons had no consistent definition of ARC, but 20 percent of respondents isolated prisoners with ARC, 23 percent did not, and 25 percent had no ARC cases. Correctional departments have developed educational seminars for staff and educational materials for inmates, but inmate information should be more specific about needle-sharing risks, safe and unsafe sex, and casual contact in prisons. 1 table and 16 references.