"As one of the responses to dramatically increasing drug scenes, heroin maintenance trials were implemented in Switzerland from 1994 onwards. The target population for this new treatment consists of heroin users who did not comply with other forms of treatment and who presented serious health and/or social problems."

Source

Ribeaud, Denis, "Long-term Impacts of the Swiss Heroin Prescription Trials on Crime of Treated Heroin Users," Journal of Drug Issues (Talahassee, FL: University of Florida, Winter 2004), pp. 186-187.