In this study, we examined the effects of two treatment techniques under on-medication and off-medication conditions on the hyperactive behavior patterns of children. Three groups of subjects were compared: a control group, a behavior modification group, and a cognitive training group. The Gordon Diagnostic System (Gordon, McClure, & Post, 1986) was used to assess the subjects at the initial screening, during treatment without medication, and during treatment with medication. The two medication conditions were counterbalanced during the second and third testing sessions. Results showed that when the cognitive intervention was combined with medication, there was a significant improvement in the subjects' ability to delay impulsive responding. However, no significant effects were seen for sustained vigilance for either the behavioral or cognitive groups. Parents rated children in the cognitive group significantly higher than those in the control group.