In 51 normal subjects (26 men, 25 women, age range 15-38 years), normal values for longitudinal axis and diameters of left and right ventricle and left and right atrium were determined by 2-D echocardiography. Both left parasternal longitudinal and cross-sectional cuts were used. Tolerance values to determine normal range were recorded, in addition to mean values and standard deviations. Diastolic and systolic diameters (DD/DS) in the left parasternal longitudinal and cross-sectional cuts gave similar results to those in the 4-chamber view from the apex: DD 2.7 +/- 0.4 (2.3-3.1) cm/m2, DS 1.8 +/- 0.4 (1.4-2.2) cm/m2, and DD 2.7 +/- 0.4 (2.3-3.1) cm/m2, DS 1.7 +/- 0.3 (1.4-2.0) cm/m2, respectively. Sizes of the right ventricle (1.8 +/- 0.4/1.4-2.2 cm/m2) and right atrium (2.4 +/- 0.5/1.9-2.9 cm/m2) could only be obtained in the 4-chamber view. Values for the left atrium (2.3 +/- 0.7/1.6-3.0 cm/m2) were obtained also in the left parasternal cross-section. Correcting for body surface, differences between males and females were reduced to the extent that there was no significant difference between them. These normal values make it possible to standardize the measurement of intracardiac dimensions by 2-D echocardiography and classify individual values.