The Los Angeles Enhanced Methadone Maintenance Project was a 5-year research demonstration project funded by the National Institute on Drug Abuse with the goal of reducing high-risk behavior for human immunodeficiency virus (HIV) among heroin users. A clinic was established for the purposes of the study and 500 clients with high-risk profiles were recruited into treatment. Follow-up assessments demonstrated that clients had reduced their drug use, criminal behavior, and HIV-risk behaviors after entering treatment. At the end of the project clients were given the option of continuing treatment at the clinic on a fee-for-service basis, transferring to another treatment provider, or undergoing detoxification. Clients who were eligible for Medicaid were likely to continue receiving methadone treatment, but those without Medicaid funding were not. The implications of terminating treatment among a high-risk population recruited into a research demonstration project are discussed.