The role of chemical dependency treatment providers and the special links between AIDS and drug use are discussed. Causes of AIDS, infection in health care workers, and HIV testing are examined, as well as the epidemiology of AIDS (who is at risk and risk by behavior, pregnancy and birth, and transfusion). The interface between AIDS and alcohol and drug use is considered, with emphasis on drugs and high-risk sex and drugs in the gay community. Issues in diagnosing and counseling persons with HIV spectrum disease are reviewed, including health care provider education, family education, and dealing with grief. The treatment of AIDS and chemically dependent patients is addressed, with particular attention paid to the fear of contagion and infection prevention. The avoidance of high-risk behavior is stressed, and the role of health care providers in helping individuals recover from AIDS and addiction is explored. Risks and benefits of HIV testing and issues in mandatory versus voluntary HIV testing are noted. Finally, liability and confidentiality issues focus on the discriminatory nature of denying treatment and on confidentiality versus public health. Appendixes contain supplemental information on universal blood and body fluid precautions issued by the Center for Disease Control and on condom use. 43 references.