Children and adolescents with aggressive disorders are prevalent in child welfare settings. Therefore, the assumption is that child welfare services would benefit from a cognitive-behavioral intervention. This study investigates whether implementation of the training with aggressive children (TAC) could improve the outcome of child welfare. Twelve children (average age 10 years), diagnosed with an oppositional defiant disorder or a conduct disorder, are treated either with a child welfare program or with a combined intervention of child welfare program and TAC. Before and immediately after completion of the combined treatment, parent and teacher ratings are collected. Parents report children participating in child welfare and TAC to show a stronger decline in social and conduct problems as well as a clearer increase in prosocial behavior. Teachers see a better improvement in social problems and tended to report a decrease in aggressive behavior. Results confirm that the TAC can enhance effects of a child welfare program. (Contains 1 note and 5 tables.)