Dynamics of the central venous pressure, superior and inferior v. cava flow and venous return following action of pressor stimuli were studied in acute experiments on anaesthetised mongrel cats with artificial lung ventilation and opened chest. The central venous pressure returned to the initial level faster as compared with the dynamics of superior and inferior v. cava flow and venous return. The superior v. cava blood flow increased more than that of inferior v. cava. The data suggest that the central venous pressure is controlled near the lower constant level.