Pragmatic randomized trial of clinical effectiveness of diagnostic testing strategies for coronary artery disease (CAD), to be performed in outpatient settings including acute and primary care and cardiology offices. Qualifying patients presenting with new or worsening symptoms suspicious for clinically significant CAD who require diagnostic testing and have not been previously evaluated will be randomized to an initial strategy of either anatomic or functional testing. All subsequent decisions regarding additional testing, medications and/or procedures will be at the discretion of the responsible clinical care team Within the functional testing arm, the subject's care team will select the specific test to be performed (exercise electrocardiogram (ECG), stress nuclear, or stress echocardiogram (echo)) consistent with 'usual care' in that practice setting. The subject's care team will be provided with 'Information sheets' summarizing current standards for test interpretation and preventive care, but specific medical treatment will not be mandated by the trial.