Objective: To examine the relationship between severity of injury and objective and subjective posttraumatic brain injury (TBI) symptomatology many years postinjury. Design: Observational, cross-sectional. Setting: Research center at an urban medical facility. Participants: 496 community dwelling adults with TBI ranging in severity from mild to severe. Participants ranged from 15–47 years postinjury. Interventions: Not applicable. Main Outcome Measures: Measures included severity of injury as measured by duration of loss of consciousness, the Brain Injury Screening Questionnaire, a 100-item self-report measure of cognitive, emotional, and physical symptoms and the Cambridge Neuropsychological Test and Automated Battery, a computerized assessment of neuropsychological functioning. Results: Results of a multivariate analysis of variance revealed no differences across levels of injury severity in self-reported memory/attention symptoms, mood symptoms, or impulsivity/dysexecutive symptoms. Differences in physical symptoms were found across severity groups such that individuals who had lost consciousness for 20 minutes to 1 day reported more physical symptoms than all other severity levels (P<.05), and the severity-physical symptom relationship reveals a curvilinear trend. These findings were maintained when time since injury was controlled for. Similarly, in a sample of 89 individuals with TBI, no differences were found in objective neuropsychological performance (on measures of processing speed, accuracy, or executive functioning) across levels of injury severity. Conclusions: The patterns of subjective and objective symptomatology observed in our cohort of individuals 15–47 years post-TBI contradict the conventional assumption that individuals with more severe injuries (as measured by loss of consciousness) experience more symptoms. This calls into question the usefulness of duration of loss of consciousness as a means of classifying TBI severity, given its inability to predict the long-term course of TBI.