The central question addressed was, how effective is parent training in reducing conduct problems in children in comparison to client-centered parent counseling? A secondary question was the relative effectiveness of the two treatment groups in comparison to a wait control group that when untreated during the 8-week period of treatment provided the other groups. Families of 36, 5- to 12-year-old conduct problem children were screened and assigned at random to treatment groups, but wait control group assignment depended upon therapist availability. Supervised graduate student therapists conducted 10 treatment sessions for each family. Parent reports and paper and pencil tests of child deviance and parent satisfaction showed a superior outcome for behavioral over the client-centered and wait control groups, and no differences between the latter two groups. At follow-up there was no maintenance of this superiority. Home observation data showed no advantage of behavioral over client-centered treatment, and these two groups did not improve significantly more than the wait control group. These results were discussed in the light of possible interactions between treatment and measurement, and methodological and sampling differences between this and other studies.