A literature review was conducted to identify research into multiple-contact (i.e. extended) telemedicine interventions for substance-use disorder. The goals were: (1) to describe the methodology used to evaluate telemedicine interventions; (2) to identify the range of interventions which have been formally evaluated; and (3) to summarize the findings. Fourteen databases and Google Scholar were searched, as well as bibliographies of relevant papers and online conference abstracts. There were 50 studies which met the inclusion criteria, of which 50% were randomized controlled trials. The studies most frequently reported the effect on substance use and 61% of those findings fully supported telemedicine interventions. Although the studies reported persistent challenges in sustaining participation, 76% of the studies reporting on satisfaction indicated that participants were enthusiastic supporters of telemedicine. Only 30% of reviewed studies addressed the effect on resource utilization. The majority of studies reported evidence of clinical effectiveness, which justifies continued research in the field.