Testing for HIV should be widely available to IV drug users. Facilities for testing should be located in drug dependency treatment centers. Strong reasons exist against a compulsory screening program. Individuals who are willing and are able to change their behavior could voluntarily submit to testing. One consequence of requiring a compulsory test as a precondition for entry into a treatment program is that participation in that program might be discouraged. Drug users share needles for social, legal, and financial reasons. Public health policies must be devised which encourage safer patterns of behavior among these people, without appearing to condone use of illicit drugs. This policy should include easier access to cost-free, sterile needles, use of intensive individual and group counseling, and public education on the health risks of HIV. Balanced against the duty of confidentiality, which is important in the areas of drug dependency and AIDS, is the obligation to protect others from transmission of HIV. Those who test for HIV take on duties owed both to the patient to keep test results confidential and to third parties to protect them from foreseeable danger of contracting the infection. There is potential for significant discrimination in the form of jobs, insurance, and housing, against drug-dependent people with HIV infection. Some States have passed statutes explicitly giving protection against discrimination based upon real or perceived HIV infection or AIDS. These statutes, together with those protecting confidentiality, provide a milieu to encourage voluntarism and cooperation among IV drug users. 10 references.