This prospective series of results and complications of coronary arteriography from the Registry of the Society for Cardiac Angiography and Interventions is the largest ever reported. Since the initial report published in 1982, the results of coronary artery surgery and angioplasty have improved and therefore older and more symptomatic patients are referred for coronary arteriography. More patients are now studied by the femoral approach, and the major complications of the techniques are similar. Despite studying older and higher-risk patients, the complications are remarkably similar to those reported in the older series. Because of the sicker patients being studied, it is probably unlikely that the complication rate will decrease further in the future. The Society for Cardiac Angiography and Interventions will continue its Registry to follow complication rates of both established and new procedure.