Several million people inject drugs of abuse and, as a result, are coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV). The treatment of this coinfected drug-abusing population is fraught with many problems such that clinicians and other health care providers have to determine whether patients should be treated first for drug addiction, for HIV/AIDS, or for HCV infection or simultaneously treated. These proceedings present the incidence and prevalence of coinfections with HIV and HCV in high-risk populations and discuss the underlying pathophysiology of coinfections and the problems and strategies of managing the treatment of coinfections among people who also inject illicit drugs. In addition, the expert panel recommended further research to determine the best possible treatment regimens applicable to injection drug users coinfected with HIV and HCV.