The temperature variation of the total hemispherical emissivities of Cu, Al, and Ag has been studied by using a temperature decay method in the 150–1000-K range. The results obtained are found to support, for the first time, a classical relaxation theory developed by Parker and Abbott. The experimental emissivity data are used to calculate the emissive relaxation times τ for Cu, Al, and Ag at various temperatures in this range. These τ values are found to be practically insensitive to temperature, a behavior contrary to that shown by the electrical relaxation times calculated from the resistivity vs temperature data of these metals.