The therapy program of the social therapeutical ward (STW) at the Pfalzinstitut for child and adolescent psychiatry was specially developed for adolescents with severe conduct disorders. Each adolescent receives a treatment program (e.g. role playing, group therapy, behavioral contracts) according to his individual problem behaviors. Essential part of the therapy program is the therapeutic milieu on the ward. Since the opening in 1990, 71 adolescents were treated more than 8 weeks at the STW. Each adolescent completed after admission and before discharge a personality questionnaire (HSPQ). The aggressive behavior during the first weeks after admission and the last 4 weeks before discharge respectively was rated by staff members on the overt aggression scale (OAS). 1 year posttreatment the behavior of these adolescents at home and at school/at work was assessed. 1 year follow-up data indicate that about 2/3 of the former patients showed no severe behavior problems at home and at school/at work respectively. Positive outcome was associated with changes from dissocial to prosocial attitudes, as measured by the HSPQ. Decrease in aggressive behavior during therapy, according to the OAS, was--contrary to expectations--associated with an increase in behavior problems after discharge. Obviously it is more promising to change the attitudes of conduct disordered adolescents in the prosocial direction than to change their overt aggressive behavior.