Research demonstrates that attention-deficit/hyperactivity disorder (ADHD) and sluggish cognitive tempo (SCT) are likely separate constructs, but no study has examined whether personality dimensions are differentially associated with ADHD and SCT. This study tested the hypothesis that sensitivity to reward would be associated with ADHD symptoms whereas sensitivity to punishment would be associated with SCT symptoms. This hypothesis was examined in a community sample of children ages 9-12 ( N= 89; 56% male). As expected, sensitivity to reward (and impulsivity/fun seeking specifically) was associated with ADHD and broadband externalizing symptoms, whereas sensitivity to punishment (and Fear/Shyness specifically) was associated with SCT and broadband internalizing symptoms. Although preliminary, these results suggest that distinct personality dimensions may contribute to the presence of ADHD/externalizing or SCT/internalizing symptoms. © 2013 Elsevier Inc.