Police officers are continually exposed to events that are psychologically and physically threatening. This places them at risk for the development of PTSD. Whether or not PTSD develops following a severely stressful event depends largely on the individual characteristics of an officer. Individual factors that increase the risk for PTSD are biological factors, such as heightened autonomic and physiological reactions, perhaps due to exposure to prior traumatic events; "historical antecedents" that include personality traits, learning patterns, socioeconomic status, the experience of child abuse, and pre-existing psychopathology; and individual social skills and coping strategies for dealing with stress. Organizational factors can also fuel traumatic stress reactions; for example, one study (Paton, Smith, Violanti, and Eranen, 2000) concluded that organizational climate was three times more influential as a predictor of traumatic stress outcomes compared with other factors. Some of these organizational factors that contribute to PTSD are lack of consultation, poor communication, and organizational conflicts. Police training programs must prepare officers for exposure to psychological and physically threatening events, help them understand the various psychological and physical reactions they may experience after encountering these events, and assist them in developing the skills and traits that will facilitate constructive reactions to these events. Further, the police organization must evaluate its organizational climate and operations in order to ensure that it helps prevent rather than promote PTSD among its officers. 2 tables and 33 references