BACKGROUND: We investigated the impact of pediatric traumatic brain injury (TBI) on attention, a prerequisite for behavioral and neurocognitive functioning. METHODS: Children aged 6 to 13 years who were diagnosed with TBI (n = 113; mean 1.7 years postinjury) were compared with children with a trauma control injury (not involving the head) (n = 53). TBI severity was defined as mild TBI with or without risk factors for complicated TBI (mild(RF+) TBI, n = 52; mild(RF-) TBI, n = 24) or moderate/severe TBI (n = 37). Behavioral functioning was assessed by using parent and teacher questionnaires, and the Attention Network Test assessed alerting, orienting, and executive attention. Ex-Gaussian modeling determined the contribution of extremely slow responses (lapses of attention) to mean reaction time (MRT). RESULTS: The TBI group showed higher parent and teacher ratings of attention and internalizing problems, higher parent ratings of externalizing problems, and lower intelligence than the control group (P < .05, >= 0.34). No effect of TBI on alerting, orienting, and executive attention was observed (P >= .55). MRT was slower in the TBI group (P = .008, d = 0.45), traced back to increased lapses of attention (P = .002, d = 0.52). The mild(RF-) TBI group was unaffected, whereas the mild(RF+) TBI and moderate/severe TBI groups showed elevated parent ratings of behavior problems, lower intelligence, and increased lapses of attention (P <= .03, d >= 0.48). Lapses of attention fully explained the negative relation between intelligence and parent-rated attention problems in the TBI group (P = .02). CONCLUSIONS: Lapses of attention represent a core attention deficit in children with mild(RF+) TBI (even in the absence of intracranial pathology) or moderate/severe TBI, and relate to daily life problems after pediatric TBI.