The effect of system pressure on gas holdup has been experimentally determined in a stirred gas-liquid reactor. The effect of increased gas density is to increase gas holdup. The contribution of the power supplied through the gas stream to the total power dissipated in the stirred vessel increases as the pressure increases, other things being equal. Bubble diameters decrease as pressure is increased. Measurements at varying pressures (and hence varying gas kinetic energies) but at constant gas volumetric flow rate and temperature were used to study the effect of kinetic energy on the characteristics of the gas-liquid dispersion. The data were correlated by a simple modification of Calderbank's equations. The equations presented reduce to Calderbank's equation at atmospheric pressure. The fact that the same correction factors enter in the equations for interfacial area, gas holdup, and bubble diameters lends confidence to the recommended equations. Since data were obtained with one small vessel only, caution is required in scaling up to larger vessels.