How much heroin maintenance (containment) in Britain?

The British policy of providing heroin legally to a few addicts at Drug Treatment Centres (DTCs) is referred to as "heroin maintenance" in America and as "containment" of heroin in Britain. Virtually unknown statistics produced by the Home Office for the United Nations are reproduced in some detail to make them widely available to professional researchers. These statistics indicate that the provision of legal heroin is very rare: about 4% of British opiate addicts at DTCs receive heroin without methadone for over one year. About 12% receive heroin and/or methadone for a year or more. The majority of British addicts are maintained on methadone only. Shifts in drugs being prescribed are due more to patient turnover than to physicians switching addicts from heroin to methadone. Implications of this data for the transatlantic debate on heroin maintenance are considered. An appendix of references on British opium policy is included.