Although naltrexone has been shown to be effective in the treatment of alcohol dependence, less is known about its efficacy when combined with different behavioral therapies. Previous work has suggested that naltrexone works best when combined with weekly cognitive behavioral therapy (CBT). This study examined the efficacy of naltrexone when combined with CBT or a motivational enhancement therapy involving less patient contact. Outpatient alcoholics (N = 160) were randomly assigned to either naltrexone (50 mg/d) or placebo and either CBT (12 sessions) or motivational enhancement therapy (4 sessions), in a 4-cell design, and treated over a 12-week period. Subjects were evaluated periodically for alcohol consumption, craving, and biologic markers of drinking (carbohydrate-deficient transferrin and gamma-glutamyltransferase). There was high retention and adherence to therapy and medication in the trial with no significant difference across the treatment groups. Naltrexone, independent of therapy assignment, increased the time to first relapse. However, the CBT-naltrexone group did better than the other groups on a variety of outcome measures. Fewer CBT-naltrexone-treated subjects relapsed, and those that did had both fewer, and more time between, subsequent relapses. This randomized controlled trial is consistent with previous reports about the utility of combining naltrexone with CBT. Despite being more efficient to administer, the combination of motivational enhancement therapy and naltrexone is less effective than CBT and naltrexone. Because CBT and naltrexone share common mechanisms of action, such as craving reduction and relapse prevention, these therapies are likely to be well suited to use in combination.