This study examined the experience of 244 mental health workers who lived and worked in New Orleans during Hurricane Katrina. An instrument, the Shared Trauma and Professional Posttraumatic Growth Inventory (STPPG), a 14-item, Likert-type scale composed of three subscales (Technique-Specific Shared Trauma, Personal Trauma, and Professional Posttraumatic Growth), was developed to understand the nature of dual trauma exposure.