Sleep disturbances and nightmares are a normal and characteristic response to trauma; however, they tend to be transient features that resolve with time. Nightmares are among the most prominent complaints of patients with post-traumatic stress disorder (PTSD). The prominence of disturbing nightmares that represent traumatic experiences in PTSD and the relationship between REM sleep and dream mentation has focused investigators on the role of this sleep stage in the disorder. Clinicians who evaluate patients with sleep disorders would be well advised to evaluate for histories of trauma and post-traumatic stress symptoms and those treating PTSD to evaluate for sleep problems including insomnia, sleep-disordered breathing, and complex sleep-related behaviors. Due to the hypothesized role for excessive noradrenergic activity in mediating sleep aspects of PTSD, the alpha-1 adrenergic antagonist prazosin was applied to treating nightmares and sleep disruption in the disorder.