The authors describe a therapist-assisted, Internet-based self-help intervention to treat posttraumatic stress disorder (PTSD) and discuss how it can be used as an efficient tool to treat large numbers of traumatized individuals. The intervention uses a modified form of stress inoculation training, promoted through daily homework assignments completed in vivo, using fewer therapist resources than standard face-to-face therapy. The process and structure of the treatment program (and structure of the Web site) and clinical and Internet security safeguards are described to introduce practitioners to a unique therapist-assisted self-management model of PTSD. It is hoped that the method described will lead to other novel, efficient methods of delivering interventions and treatment for PTSD in primary care and other outpatient and private practice settings.