Little information exists on the lifetime prevalence of traumatic events and posttraumatic stress disorder (PTSD) in the general population of the Netherlands. A national representative sample of 1087 adults aged 18 to 80 years was selected using random digit dialing and then surveyed by telephone using the Composite International Diagnostic Interview (CIDI) to determine the prevalence of trauma and DSM-IV PTSD. The lifetime prevalence of any potential trauma was 80.7%, and the lifetime prevalence of PTSD was 7.4%. Women and younger persons showed higher risk of PTSD. It was concluded that PTSD is a fairly common disorder and exposure to trauma is high throughout the population. Unexpectedly, prevalence rates resemble those found in the United States and are higher than in several other European countries.