The results of 201-Thallium myocardial scintigraphy at rest and after stress conditions in 30 patients are discussed. Among those there were 4 patients without cardiac disease, 7 patients with anterior wall scars after transmural infarction, and 19 patients with coronary heart disease and at least one coronary stenosis greater than 75%. The obtained results were compared to findings in coronary angiography and perfusion scintigraphy. The noninvasive method of 201-Thalliumscintigraphy shows a good correlation to the results of invasive investigations when performed at rest and under stress conditions. It enables greater sensivity and specifity in selection of patients with coronary heart disease compared to stress electrocardiography alone.