The overarching objective of this study is to investigate and compare the efficacy and durability of adjunct sleep-focused interventions on sleep, daytime PTSD symptomatology, and mood in a sample of 90 male and female veterans who experience nightmares and insomnia. The specific aims and hypotheses are: 1. To investigate the efficacy of prazosin, integrated behavioral sleep intervention (IBSI), and placebo (PLA) on post deployment-related sleep disturbances; 2. To compare the efficacy of pharmacological and behavioral interventions adjunct sleep focused interventions; 3. To evaluate and compare the durability of active sleep-focused interventions on sleep, daytime PTSD symptoms, mood, and anxiety by conducting a naturalistic follow-up assessment 4 months after the end-of-treatment assessment. A secondary aim is to identify demographic, psychosocial, and clinical predictors of sleep treatment response in military veterans.