 Evidence has clearly shown that methadone maintenance is not appropriate for all opioid-dependent people and that heroin is a viable maintenance drug that has shown equal or better rates of success.A committee appointed by the Norwegian government completed an evaluation of research reports on heroin maintenance treatment that were available internationally.In 2011 the committee concluded that the presence of numerous uncertainties and knowledge gaps regarding the effects of heroin treatment meant that it could not recommend the introduction of heroin maintenance treatment in Norway.