An Efficient Treatment for Posttraumatic Injury for Firefighters

The goal of this two-arm pilot randomized controlled trial is to test a behavioral intervention that integrates three evidence-based cognitive behavioral interventions (written exposure therapy; WET, cognitive behavioral therapy for insomnia; CBT-I, and cognitive behavioral therapy for nightmares; CBT-N) among firefighters. The main questions it aims to answer are: * Is the behavioral intervention feasible, acceptable, and effective in reducing symptoms of posttraumatic stress, insomnia, and nightmares? * What is the efficacy of efficient treatment vs. delayed treatment (2-4 week waitlist) in reducing symptoms of posttraumatic stress, insomnia, and nightmares? We will beta test the intervention in 1-2 groups of 3-5 firefighters. Then we will randomize 50 participants to immediate or delayed (2-4 week waitlist) treatment. Consented participants will: * Complete self-report and interview measures assessing posttraumatic stress disorder, insomnia (PTSD), and nightmares * Attend an individual treatment orientation session * Attend a 4-day (\~3 hours per day over 4 consecutive days) group treatment that integrates WET, CBT-I, and CBT-N * Attend an individual booster session held approximately one week later * Complete self-report measures before, during, and after treatment, and at a 3-month follow up assessment and a clinical interview before and after treatment to assess program efficacy.