Whilst many investigators concede that traumatic brain injury (TBI) without loss of consciousness (LOC) can occur, the number of times that this phenomena is reported in the literature is small. This case report presents an instance of TBI without LOC as supported by the observation of slowed processing speed, anosmia and a marked post-traumatic dysexecutive syndrome featuring moderately severe disinhibition. The case is discussed with a view to determining the mechanics of the blow necessary to both damage the cerebral substance yet maintain consciousness intact.