Noting that noncognitive factors may be more predictive of success in a medical career than is intellectual ability or cognitive performance, we undertook a study to determine whether a surgical personality exists and to delineate the temperament and personality traits that contribute to its definition. The Krug Adult Personality Inventory, the Strelau Temperament Inventory, and Barclay's adjective checklist were administered to 110 physicians, 35 in a "controllable lifestyle" specialty, 28 in primary care, and 47 in surgery or a surgery subspecialty. In addition, participants completed a stress inventory. Results showed that surgeons form a distinct and homogeneous group based on temperament and personality traits. We suggest that noncognitive factors can be of use to medical educators in the selection, counseling, training, and evaluation of medical personnel.