This study examined both the frequency and type of noncompliant behavior in 14 boys with co-occurring Attention-Deficit/Hyperactivity Disorder (ADHD) and oppositional defiant (OD) behavior, 24 boys with only ADHD, and 33 nonproblem boys. Mothers rated boys' noncompliant behavior on the Response Style Questionnaire (RSQ) and observers coded noncompliance during mother-son interactions. Boys with ADHD and OD behavior were noncompliant more frequently compared to boys with ADHD alone, and both groups differed from nonproblem boys. Most importantly, the types of noncompliance displayed by the ADHD/OD and ADHD boys differed. On the RSQ, mothers rated boys with ADHD/OD as having higher levels of unskilled noncompliance (i.e., covert/sneaky, overt/confrontational, emotionally labile) and lower levels of more skilled noncompliance (i.e., verbally skilled, emotionally regulated) compared to both ADHD and nonproblem boys. The observational measure focused on unskilled noncompliance and yielded a similar pattern of results, although the differences between the ADHD/OD and ADHD alone groups were not statistically significant. It is suggested that taking into account both the quantity and quality of child noncompliance may provide important information about the development of antisocial behavior in children.