The influence of solvent on the rates of acid catalysed and alkaline hydrolysis of ethyl acetate has been discussed, the main factor taken into consideration being dielectric constant of the medium. Considerable light has been thrown on the precise role of the water molecule in alkaline hydrolysis. Specific solvent effects are also clearly noticeable since the reaction velocities, for both acid and alkaline hydrolysis, are more sensitive to changes in dielectric constant in acetone-water than in dioxane-water mixtures.