In the first part of the review the authors define general principles of evaluating thallium scintigraphy of myocardium. A standard evaluation protocol is proposed. A normal picture is described and the evaluation procedure of pathological findings is outlined. A particular attention is paid to the importance of mathematical processing of data by means of a computer for increasing sensitivity of the method and reproducibility of the results. In the conclusion the authors present table with examples of normal values of quantitative analysis of thallium scintigraphy of myocardium.