This study examined cognitive/academic functioning and severity of clinical dysfunction as moderators of treatment outcome of cognitively based treatment among children (N = 120, ages 7 to 13 years) referred for aggressive and antisocial behavior. We predicted that more favorable treatment outcome would be evident among children higher in intellectual functioning, reading achievement, and level of school functioning, and with less severe and chronic symptoms of antisocial behavior and fewer symptoms across a range of diagnoses. The predictions were evaluated in relation to posttreatment behavioral problems and prosocial functioning at home and at school. Reading achievement, academic and school dysfunction, and number of symptoms across all diagnoses predicted treatment outcome. Additional analyses indicated that parent, family, and contextual factors (socioeconomic disadvantage, parent dysfunction, and adverse child-rearing practices) were related to child predictors, as well as to treatment outcome. The results convey the importance of child moderators of cognitive-behavioral treatment, as well as broader parent, family, and contextual influences in which these are embedded. © 1997 Plenum Publishing Corporation.