This Workbook, and the accompanying Therapist Guide, is designed to assist clinicians in delivering Cognitive Behavior Therapy (CBT) in a group setting to clients with PTSD. The book integrates best practices derived from group therapy literature, with evidence-based cognitive behavioral approaches targeting PTSD and frequently co-occurring conditions such as depression, anxiety, and social isolation. Group CBT has been tested with both Veteran and non-veteran populations and shown to reduce symptoms of PTSD and improve quality of life, overall functioning, and life satisfaction. The Workbook moves through the program session by session, and includes helpful information sheets, worksheets, and forms, designed to track progress and facilitate mastery of specific CBT techniques and enhance mental wellbeing. Using the exercises clients will learn how to monitor feelings, thoughts, and behaviors; confront uncomfortable emotions; and learn more effective ways of coping with their experiences.