Using a double-blind, placebo design, we evaluated 96 attention-deficit hyperactivity disordered children for the effects of methylphenidate alone and in combination with behavioral parent training plus child self-control instruction. Seventy one of the children completed the treatment protocol. As reported previously, main effects were found for medication at posttest; however, there was no evidence of additive effects. Nine months after the termination of the behavioral interventions and the withdrawal of the stimulant medication, we found limited support for the hypothesis that the combined conditions would produce greater maintenance of treatment gains than would medication alone.