Although the motion of the left ventricular wall has been examined by angiographic and by echocardiographic studies in both experimental animals and in man, there are no complete studies of the motion of the left ventricular posterior wall throughout the entire cardiac cycle. Because the posterior wall can be demonstrated echocardiographically in essentially all patients, it offers a potential of wide clinical application in the evaluation of left ventricular function. This study was undertaken to provide a detailed inclusive analysis of the motion of the left ventricular posterior wall. In 64 human volunteers the echocardiographic movements of the left ventricular posterior wall were identified. Using the R wave of the electrocardiogram as a reference and to identify phases of the cardiac cycle, each movement of the left ventricular posterior wall was temporally related to aortic or mitral valvular movements (or both). In a subset of 14 subjects, dual M-mode echocardiograms confirmed the validity of these temporal relationships. In three subjects, high-fidelity recordings from catheter tip micromanometers were made simultaneously with the echocardiogram to permit description of the temporal relationships between pressure and motion. Results of this study provide a base of normal data for comparison with the motion of the left ventricular posterior wall in a variety of diseases and in response to therapy.