Injection drug use accounts for the majority of incident and prevalent cases of hepatitis C virus (HCV) infection. However, very few injection drug users (IDUs) have received treatment for this condition given issues of medical or psychiatric co-morbidity, ongoing substance abuse and a widely held belief that such individuals will not be able to adhere to the requirements of therapy, including regular medical follow-up. With this in mind, we sought to evaluate HCV treatment uptake and outcomes among current and former IDUs attending a weekly peer support group and receiving directly observed HCV therapy. Utilizing the existing infrastructure for the management of addictive disease, we have developed a model of "one-stop shopping" whereby the treatment of addiction, HCV and other medical conditions are fully integrated, with the collaboration of nurses, counsellors, addiction specialists, infectious disease specialists, primary care physicians and researchers. Subjects interested in receiving treatment for HCV infection were referred to a weekly peer-support group and evaluated for treatment. Patients received therapy with pegylated interferon-alpha2a or -alpha2b, both in combination with ribavirin. All injections were directly observed. Overall, we observed a high uptake of HCV treatment among attendees, with 51 percent either receiving or about to receive therapy. To date, 18 patients have initiated treatment for HCV infection and 12 have completed therapy. Overall, 8/12 (67 percent) subjects achieved an end of treatment response (genotype 1, 67 percent; genotypes 2/3, 67 percent), despite ongoing drug use in 75 percent of patients during treatment. These data demonstrate that with the appropriate programs in place, a high uptake of HCV treatment can be achieved among IDUs referred to a peer-support group. Moreover, the treatment of HCV in current and former IDUs within a multidisciplinary DOT program can be successfully undertaken, resulting in ETRs similar to those reported in randomized controlled trials.