Major noncardiac surgery is a serious hazard to patients with advanced coronary disease. Perioperative infarction is common, and preliminary coronary bypass is often unwarranted. We suggest that the use of the intra-aortic balloon pump (IABP) for perioperative support of such patients makes perioperative infarction unlikely and permits otherwise hazardous operations. Three patients with advanced coronary disease (unstable angina in two) had major thoracotomies for lung masses without cardiac complications. This management plan has wider implications for other noncardiac surgical problems in such patients, particularly for mandatory operations wuch as relieving intestinal obstructions.