OBJECTIVE: The authors' objective was to explore aspects of trauma associated with severity of posttraumatic stress disorder (PTSD) in Vietnam veterans. METHOD: Several ratings of stress exposure and symptom severity were administered to 40 patients with combat-related PTSD. RESULTS: A significant relationship was observed between exposure to atrocities and the impact of PTSD on veterans' lives, as measured by the Mississippi Scale for Combat-Related Posttraumatic Stress Disorder. Exposure to atrocities was also significantly correlated with current symptom severity. In contrast, combat exposure alone was not significantly associated with overall symptom severity. Both atrocity and combat exposure, however, were significantly related to reexperiencing symptoms. CONCLUSIONS: The data suggest that the enduring effect and severity of PTSD symptoms on an individual are associated more with exposure to brutal human death and suffering than the threat of death associated with combat.