Summary: GAO discussed methadone maintenance clinics' treatment of heroin addicts. GAO noted that its review of 15 clinics in New York, California, the District of Columbia, Florida, and Texas revealed that: (1) although federal regulations required all clinics to also provide counseling and rehabilitative services, the availability and quality of such services significantly varied among the clinics; (2) while state and federal governments funded methadone treatment, many patients paid for part or all of their treatment; (3) most clinics were not able to effectively deal with such problems as addicts' use of multiple drugs or alcohol; (4) a high percentage of patients continued to use drugs after more than 6 months of methadone treatment, with heroin and other opiate drug use ranging from 2 percent to 47 percent; (5) cocaine was the most commonly used non-opiate drug, although clinics also cited serious alcohol problems among patients; and (6) clinics frequently referred patients to other agencies for employment or other services, but did not know whether patients used them. GAO believes that more information is needed to determine the potential effectiveness of the Food and Drug Administration's proposal to provide methadone, but no support services, to addicts waiting for comprehensive methadone treatment and who are at high risk for contracting Acquired Immunodeficiency Syndrome through shared needle use.