As the availability of electron-beam CT increases, it is appropriate to question the balance among medical science, patient care, and profits. Broadening patients' sense of empowerment and promoting their autonomy are worthy goals within medicine. Breast-cancer screening with mammography is an example of a radiographic test used successfully in a diagnostic program based on self-referral. But the lessons of such a program, in which the distinction between the disease and the disease-free state is more easily recognized than is the case for age-dependent calcific arterial changes, are not easily extrapolated to screening for coronary disease. Currently, we are facing the possibility that market forces may increase interest in electron-beam CT beyond what is justified by its potential medical benefit. Well-designed clinical trials are required to define fully the appropriate indications for and limitations of electron-beam CT. Such trials will eventually clarify the medical applications of the technique and determine its suitability as a screening procedure for cardiovascular disease. Until then, the use of electron-beam CT, like that of all tests in medicine, should be based on a clearly defined rationale and should be coupled with a medical evaluation by a physician.