The study examined simulating and non-simulating subjects' self-report of 10 common cognitive, emotional, and physical symptoms on the Postconcussion Symptom Checklist (PCSC). Sixty undergraduate subjects were randomly assigned to either a control group instructed to report symptoms honestly or one of two simulating groups: a naive simulating group instructed to feign believable symptoms or a sophisticated simulating group that was given additional information about possible cognitive, emotional, and physical sequelae associated with traumatic brain injury (TBI). These three groups were compared to a group of 20 subjects with postconcussion symptomatology (PCS) of at least 3 months duration following a motor vehicle accident. Mean PCSC total scores and summary scores for symptom frequency, intensity and duration for the control group were significantly lower than scores for the other groups. Simulating groups did not differ from each other or from the PCS group. Thus, simulating subjects were able to report postconcussion symptoms at a similar frequency, intensity, and duration when compared to subjects experiencing postconcussion symptomatology. Implications of these findings when evaluating self-reported postconcussion symptoms endorsed by patients as evidence of TBI are discussed.