A small population of chronic heroin users, once thought to be ‘untreatable’, is now benefiting from a novel type of therapy using medicinal heroin as the substitution drug. In a new report out today from the EU drugs agency (EMCDDA), experts describe the development as ‘an important clinical step forward’. The report, New heroin-assisted treatment, provides the first state-of-the-art overview of research on the subject, examining the latest evidence and clinical experience in this area in Europe and internationally.