The study was undertaken to test the hypothesis that time-limited group psychotherapy, led by therapists who offer high accurate empathy and nonpossessive warmth, would produce significant change in delinquent behavior. The obtained results support this hypothesis. Significant superiority of the treated subjects, as compared with a control group, was demonstrated in percentage of time spent out of institution during a 1-year follow-up, as well as on the "C" scale of the Minnesota Counseling Inventory (MCI) which was specifically designed to differentiate delinquents from nondelinquents. A major mediating effect of therapy was to change self-concepts in a positive direction which increased the congruence between the self and the ideal self. Group psychotherapy also had significant positive effects upon attitudes toward parents and siblings.