Sleep disturbance is common after traumatic brain injury (TBI). Insomnia, fatigue, and sleepiness are the most frequent post-TBI sleep complaints with narcolepsy (with or without cataplexy), sleep apnea (obstructive or central), periodic limb movement disorder, and parasomnias occurring less commonly. In addition, depression, anxiety, and pain are common TBI comorbidities with substantial influence on sleep quality. Diagnosis of sleep disorders after TBI may involve polysomnography, multiple sleep latency testing, or actigraphy. Treatment is disorder-specific and includes the use of medications, continuous positive airway pressure, or behavioral modifications. Unfortunately, treatment of sleep disorders associated with TBI often does not improve sleepiness or neuropsychologic function.