CT-EXTRA is a randomized clinical trial that will compare a novel diagnostic strategy employing the addition of coronary MSCT angiography to exercise treadmill testing with a standard diagnostic strategy of exercise treadmill testing for the outpatient evaluation of low-intermediate risk patients with possible angina. This is the first randomized clinical trial that evaluates a diagnostic strategy for outpatient chest pain that incorporates a noninvasive assessment of both coronary artery function and anatomy. CT- EXTRA will determine whether coronary MSCT angiography adds any incremental prognostic value over exercise treadmill testing alone for predicting future adverse cardiac events and reduces downstream clinical resource utilization. This study will also evaluate the impact of this strategy on the avoidance of unnecessary invasive coronary angiography, statin and aspirin prescription, patient anxiety, satisfaction with the diagnostic approach, and motivation for healthy behavioral change. Finally, an economic analysis will be performed to assess the differences in overall healthcare costs between the diagnostic approaches. In today’s managed care-dominated paradigm, it is paramount that a new diagnostic modality such as coronary MSCT angiography is not only clinically effective but cost effective as well. CT EXTRA will provide critical information to clinicians and health care administrators on the clinical and cost effectiveness of an initial diagnostic strategy employing routine coronary MSCT angiography in the evaluation of patients for possible angina.