CBT4CBT (computer based training in cognitive behavioral therapy) covers seven key cognitive behavioral skills, or ‘modules’, (functional analyses, coping with craving, refusing offers of drugs or alcohol, problem solving skills, recognizing and changing thoughts, decision making skills, and HIV/HCV risk reduction). Each of the seven modules follows a common format, roughly parallel to a traditional CBT session; check-in and review of homework, introduction of the skill to be taught in that module, a video vignette depicting an actor in a challenging situation, teaching of the skills, demonstration of the skill through another vignette with the same actor using the skill to avoid substance use, demonstration of practice exercise by the actor, a walk-through of the practice exercise, and a short quiz to test understanding of the skill.