It is widely recognized that neuropsychiatric disturbances contribute substantially to disability among persons with traumatic brain injury (TBI). This issue of Psychiatric Clinics addresses the most common and the most clinically challenging neuropsychiatric sequelae of TBI. The overarching aim of this publication is to provide clinicians with information about the clinical characteristics, diagnostic assessment, neurobiology and treatment of these conditions that will be useful in their work with individuals and families affected by TBI. Topics include: Posttraumatic Encephalopathy; Cognitive Disorders after TBI; Emotional and Behavioral Dyscontrol after TBI; Mood Disorders following TBI; Apathy following TBI; Psychotic Disorders following TBI; Sleep and Fatigue following TBI; TBI and Posttraumatic Stress Disorder; Neuropsychiatry of Persistent Post-concussive Symptoms; Psychiatric Disorders following Pediatric TBI.