For patients with chest discomfort, noninvasive cardiac testing can be used for the diagnosis of acute coronary syndrome and for the evaluation of the risk of future cardiovascular events and disease severity in patients with known coronary artery disease. Clinical prediction rules can guide risk assessment for patients with acute or stable chest discomfort. For acute chest discomfort, patients with low risk do not need urgent testing, and those at high risk should have invasive coronary angiography. For acute chest discomfort in patients at intermediate risk, exercise stress testing can provide useful prognostic information on the likelihood of future mortality and survival despite modest sensitivity and specificity for coronary artery disease. Exercise or pharmacologic stress testing with imaging allows dynamic assessment of ventricular function and perfusion. For stable chest discomfort in patients with low risk, coronary artery calcium scoring can be used to exclude calcified plaque or exercise stress testing can be used for the evaluation of future cardiac risk and prognosis. For stable chest discomfort in patients with intermediate or high risk, exercise stress testing or stress testing with imaging (ie, echocardiography, myocardial perfusion imaging, or cardiac magnetic resonance imaging) may be used for the evaluation for myocardial ischemia.