Various theoretical models, proposed for correlating glass durability with its composition, have been examined for a wide variety of silicate, borosilicate and alumino silicate glasses. Comparisons are made between the predictions of these models and those of an empirical formulation extracted from existing data in the present work. According to the authors, the empirical approach provides independent confirmation of the relative accuracy of the silica release rate predictions of the different theoretical models in static leaching systems. Extensions of the empirical aproach used here to provide further information is proposed and discussed. Tables, correlation data, 23 references.