The recent availability of two-dimensional echocardiography (2DE) has fostered the expectation that cardiac embolic sources could be identified or excluded with certitude in ischemic stroke patients. As a screening procedure, 2DE has had a low yield. In selected patients, 2DE holds promise as a useful diagnostic test. Stroke patients who may benefit from 2DE include patients under age 45, patients with suspected left atrial myxoma, and patients with known infective endocarditis, prosthetic heart valves, or rheumatic valvular heart disease. In patients with ischemic heart disease, the yield of useful information from 2DE will be low but may, on occasion, influence management.