Recent experiments have measured the rate of thermalization due to electron-electron scattering in GaAs at excitation densities below 10 15 cm -3 . Below approximately 5×10 13 cm -3 , the rate of thermalization becomes independent of the carrier density. This paper shows that numerical solution of the Boltzmann equation for the evolution of the electron-energy distribution via Coulomb scattering, assuming self-consistent quasistatic screening and an isotropic distribution of electrons, yields the experimental values for thermalization rate at all densities below 10 15 cm -1 using only known constants of GaAs with no adjustable parameters