A dimensionless correlation for the liquid overflow rate from a rising column of foam has been developed that expresses the ratio of liquid to gas superficial velocities as a function of Reynolds, Grashof, and Morton numbers. This correlation is developed using new and previously reported data. An empirical approach is made after noting that models that estimate the overflow rate by adding a gross upward velocity to conventional solutions of stationary foam drainage that take into account viscous losses only at the Plateau border walls are unsatisfactory. Relaxation of the assumption of rigid Plateau borders by allowing for finite surface shear viscosity does not improve such a mechanistic approach. However, an existing semiempirical drainage expression that takes into account losses at the vertices within the foam enables a much better prediction of the overflow rate, although the newly developed correlation gives superior predictions and requires no a priori knowledge of the drainage behavior of the foam. Experiments performed on a shear-thinning solution are also discussed.