The role of exposure to a human-made disaster and the subsequent development of post-traumatic stress reactions were examined. Subjects included 49 males and 30 females who were variously exposed to the Luby's shooting incident in Killeen, Texas in October of 1991. Post-traumatic stress symptomatology was measured by the SCL-90R. Exposure was operationalized by using a scenario-rating scheme with independent raters estimating each subject's level of exposure. A regression and commonality analysis revealed that exposure is an important predictor in post-traumatic symptomatology. Premorbid functioning and gender were also found to play important roles, with females expressing higher levels of symptomatology.