The predictive value of initial bicycle ergometry was assessed on the basis of long-term follow-up (averaging 5.4 years) of 272 patients with stable angina pectoris. The prognosis for anginal patients was shown to be basically worse where the threshold capacity, operation volume at the final stage of exercise and the double product at the time of an anginal attack were at low levels. It was also unfavorable in cases where electrocardiograms showed combinations of horizontal ST depression and frequent extrasystoles or ambidirectional ischemic displacements in individual leads, during an anginal attack provoked by rationed exercise. These parameters are suggested as criteria for dividing anginal patients into high and relatively low risk groups with respect to the fatal outcome.