This study is a randomized controlled trial to determine the efficacy of a "peer-volunteer activism" intervention to reduce distributive syringe and injection paraphernalia sharing behaviors among HCV positive IDUs and promote the uptake of HCV care and treatment. If proven effective, this intervention would substantially decrease the risk of HCV infection in the community. To address these aims, we plan to recruit, screen, and randomly assign 750 IDUs age 18-35 years who are HCV-seropositive but HIV-seronegative in Baltimore, New York and Seattle to a behavioral intervention (250 per site), and prospectively monitor participants behavior at 3- and 6-month follow-up visits.