This case report addresses assessment and treatment considerations for a patient suffering from posttraumatic stress disorder (PTSD) in the context of mild traumatic brain injury and ongoing pain. Management of this case is based on the application of evidence-based therapy, and of cognitive behaviour therapy, for PTSD reduction. Assessment and treatment approaches recognize that delivery of treatment requires modification to allow exposure therapy for individuals who are partially amnesic of their traumatic experience. Further, administering exposure and cognitive therapy for patients with cognitive impairment requires specific means of treatment delivery to allow adequate compliance with therapy tasks. This case highlights that evidence-based approaches can be usefully applied to complex presentations but they may require modifications that recognize obstacles associated with comorbid conditions.