The diagnosis of posttraumatic stress disorder (PTSD) sometimes is raised in compensation claims, in tort settings, and in other medical-legal settings. Accordingly, health-care and legal professionals working in these areas need to be familiar with the current findings and controversies concerning the disorder. The purpose of this article is twofold. First, we review the most important findings concerning the clinical features, etiology, and treatment of PTSD. Second, we examine six major controversies concerning the disorder that are relevant to psychologists and other medical-legal practitioners: (a) the issue of what qualifies as a traumatic stressor, (b) the question of whether traumatic stress causes brain damage, (c) the validity of the concept of delayed-onset PTSD, (d) the recovered memory controversy, (e) the question of whether PTSD can arise when the person has no memory of the trauma (e.g., due to concussion), and (f) issues concerning PTSD malingering. Throughout this article we offer recommendations for psychological and other medical-legal practice in relation to the evaluation of PTSD claims.