Questionnaires and psychological tests were used to assess the psychosocial impact of mandibular prognathism. Patients with mandibular prognathism were asked to assess the impediments caused by their dentofacial deformity. In addition, they were asked to rate their appearance and to repo rt the effect that it had on their social contacts. The self-assessment revealed that patients felt esthetically impaired, but that they had a fairly positive autosterotype, as revealed by their self-descriptive choices on a personality scale. These results were compared with the assessments made by two different control groups composed of persons with no esthetic impairment. The attitudes of the control groups toward the patients were more negative than perceived by the patients, indicating that mandibular prognathism does result in a social handicap.