Objective: Empirically based studies have demonstrated that prolonged exposure therapy effectively reduces posttraumatic stress disorder (PTSD) symptoms in a vast range of traumas, yet reports of the efficacy of such therapies in combat- and terror-related PTSD are scarce. In this article, we examine the efficacy of prolonged exposure therapy in combat- and terror-related PTSD in comparison to treatment as usual (TAU). Method: Between July 2002 and October 2005, 30 patients of a trauma unit within a psychiatric outpatient clinic were recruited and randomized into prolonged exposure versus TAU therapies. Patients were diagnosed with chronic PTSD (Mini-International Neuropsychiatric Interview criteria) related to combat- (n = 19) or terror-related (n = 11) trauma. Main outcome measures included symptoms of PTSD and depression, as measured by the PTSD Symptom Scale-Interview Version and the Beck Depression Inventory. Results: Posttraumatic stress disorder symptom severity was significantly lower in patients who received prolonged exposure therapy in comparison to patients who received TAU (F1,24 = 35.3, P < .001). Similar results have emerged in measures of depression and state and trait anxiety. In addition, a significant change from pretreatment to follow-up was found for the prolonged exposure group (F1,14 = 80.5, P < .0001), but not for the TAU group (F1,10.3 = 0.6, P = .44). Conclusions: Findings indicate that, similar to PTSD related to other types of trauma, prolonged exposure therapy is beneficial in the amelioration of combat- and terror-related PTSD symptoms. In addition, prolonged exposure was superior to TAU in the short- and long-term reduction of PTSD and depression symptoms. Trial Registration: clinicaltrials.gov Identifier: NCT00229372.