Among the many diagnostic and therapeutic uses of ionizing radiation in medicine, the potential for misuse is greatest in diagnostic imaging, particularly with computed tomography. While several technical adjustments may be made to produce a dose that is as low as reasonably achievable, appropriate utilization of these tests is a more difficult issue to address. The risks of ionizing radiation, taking into account the patient's age, sex, and body part to be examined, must be balanced with the potential benefit that comes with medical imaging. Fortunately, the benefits outweigh the risks in most clinical scenarios, particularly in patients without a confirmed diagnosis. However, the repetitive imaging of patients with known clinical conditions to assess for interval change may pose the greatest opportunity to curb over-utilization of imaging tests that may be harmful. The medical community at large must be educated in the effects of ionizing radiation. Moreover, practitioners must be inspired to differentiate imaging tests for primary diagnosis from those performed in follow-up of known pathology in common diagnostic algorithms. This metamorphosis must extend from the most senior health care administrator to the most junior healthcare professional and must include those who are charged with acquiring the necessary imaging tests. In addition, imaging professionals must avail themselves of the numerous technical advances that allow a reduction in the dose of ionizing radiation that is associated with common imaging procedures. And, dose monitoring must be performed on many levels, including the dose to an individual patient undergoing a specific imaging test.