As managed care organizations move from cost cutting to cost-effective treatment, greater emphasis will be placed on utilization of documented, effective psychotherapies. Externalizing disorders in children, including attention-deficit disorder and oppositional-defiant disorder, comprise the most frequent referrals to outpatient clinics. Of available psychosocial treatments, parent training and child social-skills training have established efficacy in research settings. But in community settings, these approaches are not often systematically used, and rarely have they been shown to be effective. In a hospital-affiliated child psychiatry clinic located in an upper-middle-class community, parent and child group programs were set up to be the standard initial treatment for these disorders for children ages 5 to 11. Using the Eyberg Checklist for pre- and postmeasures, 55 patients who completed treatment showed an average treatment effectiveness of 0.89 standard deviations on the intensity score, which is comparable to outcome data from research studies of efficacy. This would indicate that these programs have effectiveness in a standard clinic setting that is comparable to their efficacy in research intervention programs.