The relative values of imaginal and real-life exposure exercises were tested in this study by randomizing 14 patients who met DSM-III-R criteria for PTSD at least 6 months after the initiating trauma to one of two groups. Group 1 (n = 7) had four, weekly, hour-long sessions of imaginal exposure followed by four, weekly, hour-long sessions of live exposure. Group 2 (n = 7) had the reverse order of four live exposure sessions followed by four imaginal exposure sessions. both groups improved significantly on both PTSD-specific measures and measures of general health post-treatment, and significantly further on 7 out of 12 measures at follow up 12 months post-treatment. Clinical improvement was in the older of 65-80% reduction in target symptoms. On one measure only (problem 2--phobic avoidance), live exposure yielded more improvement than imaginal exposure whether given first or second. The importance of both live and imaginal exposure to all relevant cues, behavioral and cognitive, is discussed, together with the value of self-exposure homework for patients with PTSD.