Research has suggested that rescue workers are at increased risk for psychological distress. To determine whether 9/11 deployment was a significant risk factor for canine search and rescue handlers, 82 deployed handlers were compared to 32 nondeployed handlers on measures of posttraumatic stress disorder (PTSD), depression, anxiety, acute stress, and clinical diagnoses. Deployed handlers reported more PTSD and general psychological distress 6 months after 9/11. Among deployed handlers, prior diagnoses and peritraumatic reactions were associated with psychological distress whereas social support and training were protective. Results suggest that more extensive screening and prophylactic interventions for individuals with a history of mental illness could be beneficial. Future research should examine identified risk/resilience factors prospectively, and training and intervention should be designed accordingly.