Background: Surgical teams have not had a routine, reliable measure of patient condition at the end of an operation. We aimed to develop an Apgar score for the field of surgery, an outcomes score that teams could calculate at the end of any general or vascular surgical procedure to accurately grade a patient's condition and chances of major complications or death. Study design: We derived our surgical score in a retrospective analysis of data from medical records and the National Surgical Quality Improvement Program for 303 randomly selected patients undergoing colectomy at Brigham and Women's Hospital, Boston. The primary outcomes measure was incidence of major complication or death within 30 days of operation. We validated the score in two prospective, randomly selected cohorts: 102 colectomy patients and 767 patients undergoing general or vascular operations at the same institution. Results: A 10-point score based on a patient's estimated amount of blood loss, lowest heart rate, and lowest mean arterial pressure during general or vascular operations was significantly associated with major complications or death within 30 days (p < 0.0001; c-index = 0.72). Of 767 general and vascular surgery patients, 29 (3.8%) had a surgical score ≤ 4. Major complications or death occurred in 17 of these 29 patients (58.6%) within 30 days. By comparison, among 220 patients with scores of 9 or 10, only 8 (3.6%) experienced major complications or died (relative risk 16.1; 95% CI, 7.6-34.0; p < 0.0001). Conclusions: A simple score based on blood loss, heart rate, and blood pressure can be useful in rating the condition of patients after general or vascular operations.