Dr. Lazar Greenfield observes the conundrum that there are many standards a physician must comply with to become a surgeon, but no set standards for when a surgeon should retire. Host Dr. Mark Nolan Hill speaks with Dr. Greenfield, professor in the division of cardiovascular medicine at the University of Wisconsin School of Medicine and Public Health and director of the preventive cardiology program and vascular health screening program at the University of Wisconsin Hospital and Clinics, regarding his longitudinal study on the abilities and self-perception of aging surgeons.