Cognitive Behavioral Therapy (CBT) for Nightmares in Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) Veterans

Inclusion Criteria: * Currently enrolled in treatment in the Michael J. Crescenz VA Medical Center or VA Connecticut Healthcare System Mental Health Clinic * Meets DSM-IV-R criteria for current PTSD (within the past month) * Repetitive, military-related nightmares (at least 1 every 2 weeks, for at least 6 months) * A global sleep disturbance, as indicated by a score of five or greater on the Pittsburgh Sleep Quality Index * Ability to read and speak English * A concurrent anxiety disorder or depressive disorder diagnosis will be allowed * Dementia related to head injury and amnestic disorder related to head injury will be allowed Exclusion Criteria: * Current substance dependence * Bipolar disorder * Delirium * Dementia that is not related to head injury * Amnestic disorder that is not related to head injury * Schizophrenia and other psychotic disorders * Severe traumatic brain injury, as indicated by self-report (loss of consciousness or alteration of mental status greater than 24 hours, or peri-traumatic memory loss, or any posttraumatic amnesia greater than 7 days) * The presence of diagnosed sleep disorders other than insomnia: narcolepsy, circadian rhythm sleep disorders, and periodic limb movement disorder. Participants in treatment for sleep apnea, or who have not benefited from or declined available treatment may be included.