Evaluation of the results of surgery for coronary artery disease requires a knowledge of the clinical course of patients not having this mode of treatment. To obtain such information we performed a retrospective analysis of the fate of 266 patients with arteriographically documented significant stenosis following from one to ten years. For the entire group the five year survival was 73%. Subdivided into single, double or triple vessel disease categories the percent five year survival rates were respectively 92, 65 and 55. A history of angina pectoris or myocardial infarction prior to angiography did not affect survival. However, hypertension, congestive heart failure, abnormal hemodynamics or left ventricular asynergy were all associated with a diminished five year survival, the values being respectively 61%, 38%, 62% and 58%. These results should be of VALUE IN ASSESSING THE PROGNOSIS OF NONSURGICALLY TREATED PATIENTS WITH CORONARY ARTERY DISEASE.