The Independent Working Group on Drug Consumption Rooms was set up to take an objective, evidence-based approach to a sensitive question: should problematic drug users be provided with a place to go to use their illegally obtained drugs in a clean environment, supervised by medically trained staff? In order to address this question, the Independent Working Group (IWG) spent 20 months assessing the evidence. It commissioned comprehensive reviews of the research on the harms associated with drugs in the UK and the effectiveness of drug consumption rooms (DCRs) abroad, and authoritative papers on the national and international legal situation. Where there were gaps in the evidence base, research projects were commissioned and the IWG heard evidence from drug users’ groups and people involved in developing local plans for DCRs in the UK. Members also visited a number of DCRs abroad to find out how they operated in practice.