This study examined the frequency of reexperiencing, avoidance, and hyperarousal symptoms most often associated with posttraumatic stress disorder (PTSD) among 45 persons with social anxiety disorder and 30 nonanxious controls in response to an extremely stressful social event (which did not satisfy DSM-IV's PTSD Criterion A). Avoidance and hyperarousal in response to reminders of socially stressful events were common among patients; more than one-third would have met criteria for PTSD if these events satisfied DSM-IV PTSD Criterion A. Frequency of this PTSD-like symptom pattern did not differ among patients who did and did not experience another event that did satisfy PTSD Criterion A. Implications of these findings for the treatment of social anxiety disorder are discussed.