Posttraumatic stress disorder (PTSD) is a condition that can be easily malingered for secondary gain. For this reason, it is important for physicians to understand the phenomenology of true PTSD and indicators that suggest an individual is malingering. This paper reviews the prevalence of PTSD for both the general population and for specific events, such as rape and terrorism, to familiarize evaluators with the frequency of its occurrence. The diagnostic criteria for PTSD, as well as potential ambiguities in the criteria, such as what constitutes an exposure to a traumatic event, are reviewed. Identified risk factors are reviewed as a potential way to help differentiate true cases of PTSD from malingered cases. The question of symptom overreporting as a feature of the disease versus a sign of malingering is discussed. We then examine how the clinician can use the clinical interview (e.g., SIRS, CAPS), psychometric testing, and the patient's physiological responses to detect malingering. Particular attention is paid to research on the MMPI and the subscales of infrequency (F), infrequency-psychopathology (Fp), and infrequency-posttraumatic stress disorder (Fptsd). Research and questions regarding the accuracy of self-report questionnaires, specifically the Mississippi Scale (MSS) and the Personality Assessment Inventory (PAI), are examined. Validity, usability, and cutoff values for other psychometric tests, checklists, and physiological tests are discussed. The review includes a case, which shows how an individual used symptom checklist information to malinger PTSD and the inconsistencies in his story that the evaluator detected. We conclude with a discussion regarding future diagnostic criteria and suggestions for research, including a systematic multifaceted approach to identify malingering.