This project is based on the principles of 'harm reduction', i.e., if it is not (yet) possible to cure a hard drug user, one should at least try to minimize the harm they cause to themselves and their environment. As soon as a client refrains from the use of illegal drugs, the client can 'graduate' to other methadone programs with a higher threshold. To prevent double prescription, all Amsterdam methadone programs participate in the central methadone registration. The Amsterdam Municipal Health Service has contact with over 50 percent of the drug users. The estimated number of hard drug users has remained stable over the last 5 years, while the average age of drug users has increased to 32 years. In the future, increasing the average dosage and the provision of injectable drug users will be discussed to assess their role in further harm reduction. 10 references (Author abstract)