Inclusion Criteria: Participants will be recruited from the population of Operation Iraqi Freedom/Operation Enduring Freedom veterans referred to the Posttraumatic Stress Disorder (PTSD) clinic for evaluation and treatment, and volunteers participating in the Mental Illness Research, Education and Clinical Centers (MIRECC) registry who agreed to be recontacted for future studies. All study participants will have: 1) provided informed consent; 2) utilize Durham VA Medical Center health care services as their primary source of health care; 3) will meet the Diagnostic and Statistical Manual (DSM-IV-R) criteria for a diagnosis of PTSD; 4) will screen positive for an Insomnia Disorder on the Duke Structured Sleep Interview for Sleep Disorders (DSISD); 5) and will score greater than 14 on the Insomnia Severity Index (ISI).