Dublin has an estimated 13,460 opiate drug users. The role of general practice in providing care for this group has increased over the last four years. A Central Methadone Treatment List (CMTL) registers all clients currently on treatment. To obtain a social, demographic and drug using profile of opiate users attending general practitioners (GPs) for methadone maintenance. A cross sectional survey of opiate users attending general practice for methadone maintenance in the Dublin area in early 1999. Data was collected on 571 clients (62% of total number attending general practice), of whom 97% had used heroin in the past and 12% had never injected. Although clients had been receiving methadone maintenance in general practice for a mean of 14 months, 16% were still using heroin, of whom 31% were still injecting. The mean age of first drug use was 15.5 years and of first injecting was 19.4 years. Younger clients are starting both to use drugs and inject drugs at an earlier age. Record keeping was good, with most items of information present in over 70% of the charts surveyed. A total of 17% of clients recorded on the CMTL could not be traced to the GP recorded as providing care. Despite treatment with methadone maintenance, there is a high level of continued risk activity in this group. Furthermore, a trend towards earlier initiation to drug use is apparent. The CMTL registration process requires further exploration.