This study evaluated the clinical significance of measuring between session parental adherence on child and parent outcomes for 51 children (age 4 to 8.5 years) with attention deficit/hyperactivity disorder (ADHD) in a multimodal group training program. Three group treatment conditions: (a) child-only treatment (C1), (c) child and parent training (C2), and (c) C2 + Parent Adherence Measure [PAM (C3)] were compared to assess the clinical significance of measuring parental adherence on child behavioral problems, socialization skills, and parental efficacy. Parents administered the PAM (C3) displayed, in general, better outcomes on child and parent measures than the other two conditions. Results suggest that a multimodal group training program for young children with ADHD is favorable to child group training only. This study offers preliminary support for the clinical utility of measuring parental adherence in a child ADHD multimodal group training program. (Contains 2 tables and 2 notes.)