Of the 3188 doctors surveyed, 1650 responded. About half of the doctors (49%) supported governmental legislation to establish national health insurance, and 40% opposed it. A little over one quarter of doctors (26%) supported a program in which the federal government would pay for all health care. Doctors were most likely to support national health insurance if they practiced in inner cities or nonprivate settings and if at least 20% of their patients were on Medicaid. The types of doctors with the highest support for national health insurance were internal medicine doctors, pediatricians, and psychiatrists. Support was lowest among family medicine doctors, anesthesiologists, and specialty surgeons.