The study found that penitentiary workers' experiences of workplace violence, whether committed by detainees or co-workers once or more than once, was not apparently linked with a diagnosis of PTSD; however, workers who were victims of aggression and/or violence during the past 12 months were more at risk of exhibiting posttraumatic stress symptoms. Among these individuals, posttraumatic symptoms were more likely among workers with type D personalities, i.e., those who tend to avoid attachments and social interaction. Findings showed strong correlations between negative affectivity and posttraumatic stress and between type D personality and posttraumatic stress. In turn, absenteeism was related to the presence of symptoms of posttraumatic stress. The study concludes that it is possible to reduce the amount of absenteeism among penitentiary workers by preventing posttraumatic stress. Talking to colleagues about experiences of aggression and violence was found to protect victims from developing posttraumatic stress symptoms. Study participants were 174 penitentiary workers employed in 1 of the penitentiaries of the Judicial Penitentiary Services; 54 reported having been victims of aggression and violence in the workplace during the past 12 months. Structured interviews consisted of 29 questions that solicited responses on sociodemographics, experiences of violence on the job from detainees and coworkers, reactions to aggression/violence, and absenteeism. Three questionnaires measured symptoms of PTSD, attachment style, and type D personality. 5 figures, 1 table, and 64 references