This study examined the relationship of parental trauma exposure and PTSD to the development of posttraumatic stress disorder (PTSD), depressive and anxiety disorders in the adult offspring of Holocaust survivors. One hundred and thirty-five subjects (55 men and 80 women) were divided into three groups according to parental trauma exposure and PTSD: 60 subjects were offspring of Holocaust survivors who endorsed having at least one parent with PTSD, 33 were offspring of Holocaust survivors who reported having no parent with PTSD, and 42 were demographically similar subjects with no parental Holocaust exposure. All subjects underwent a comprehensive psychiatric interview in which information about lifetime psychiatric diagnoses and exposure to traumatic events was obtained. Subjects also completed a checklist based on the 17 DSM-IV symptoms of PTSD, to estimate the symptom severity of PTSD in their parents. A presumptive diagnosis of parental PTSD was assigned according to DSM-IV criteria. Forward and forced entry stepwise logistic regression analyses were used to determine the effects of parental exposure, parental PTSD, and the subject's own history of trauma in the development of PTSD, depressive, and anxiety disorders in the offspring. The findings demonstrate a specific association between parental PTSD and the occurrence of PTSD in offspring. Additionally, parental trauma exposure, more than parental PTSD, was found to be significantly associated with lifetime depressive disorder. The identification of parental PTSD as a risk factor for PTSD in offspring of Holocaust survivors defines a sample in which the biological and psychological correlates of risk for PTSD can be further examined.