Abstract Optimal therapy for Posttraumatic Stress Disorder (PTSD) follows logically from an understanding of etiological models describing the development and maintenance of the disorder. Accordingly, the present article provides a brief overview of PTSD with particular attention paid to etiology. Exposure-based interventions have consistently been shown to promote superior posttraumatic adjustment relative to alternate treatment approaches. In addition to describing exposure therapy for PTSD, we briefly review the supporting treatment-outcome literature. Misconceptions surrounding exposure therapy are presented and discussed. Finally, cultural considerations and complex presentations are considered. Keywords: Posttraumatic Stress Disorder (PTSD), peritraumatic reaction, intense fear, helplessness, horror ********** In order to meet diagnostic criteria for posttraumatic stress disorder (PTSD), an individual must experience, witness or be confronted with an event that involves actual or threatened serious injury or death, or a threat to the physical integrity of self or others. Further, the peritraumatic reaction to the event must involve intense fear, helplessness or horror (American Psychiatric Association; APA, 2000, pp.467). Although resiliency in the face of trauma is the norm, exposure to events that may potentially elicit PTSD is not uncommon. By way of example, one large scale epidemiological study of nearly 6,000 U.S. citizens indicated that approximately 61% of men and 51% of women have experienced at least one potentially traumatic event in their lives (Kessler, Sonnega, Bromet, Hughes, & Nelson, 1995). Events that frequently precipitate PTSD include combat, natural disasters, sexual assault, violent crime, or witnessing or experiencing significant accidents or injuries. According to the most recent version of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR; APA, 2000), in order for an individual to meet diagnostic criteria for PTSD he or she must have at least one symptom of re-experiencing, three or more avoidance symptoms, and two or more persistent symptoms of heightened arousal related to traumatic exposure. Re-experiencing may include recurrent and intrusive distressing recollections of the event, recurrent dreams of the event, acting or feeling as if the event were re-occurring, intense psychological distress at exposure to internal or external cues which represent the event, or physiological reactivity with exposure to internal or external cues that represent an aspect of the event. The second symptom cluster, characterized by avoidance, involves efforts to avoid thoughts, feelings, conversations, activities, places or people that are associated with recollections of the trauma, an inability to recall important aspects of the trauma, diminished interest in activities, feelings of detachment from others, a restricted range of affect, or a sense of a foreshortened future. The hyperarousal symptoms that constitute the third cluster include difficulty falling or staying asleep, irritability or outbursts of anger, difficulty concentrating, hypervigilance, and an exaggerated startle response. In order to meet diagnostic criteria for PTSD the symptoms outlined above must persist for at least one month following the trauma and must significantly interfere with an individual's social, educational, or occupational functioning. Although exposure to potentially traumatic events is not uncommon in the general population, results from the National Comorbidity Survey indicate that PTSD affects only 7.8% of the population, with the rate for women (10.4%) being more than twice the rate for men (5.0%) (Keane & Barlow, 2002; Kessler et al., 1995). It is important to note that the elevated rate of PTSD for women is most likely due to the increased rate of victimization among women. In a national study of exposure to crime among women in the United States, 36% of women reported being directly affected by crime at some point in their lives, with rape or molestation being the most frequently experienced crime (Keane & Barlow, 2002; Resnick, Kilpatrick, Dansky, Saunders, & Best, 1993). …