A combined flow technique for study of sorption properties of clay materials has been developed. First, water desorption is recorded and, subsequently, simultaneous measurements of water adsorption and of clay-bed expansion are performed. The technique is expected to become a powerful tool for determination of the generic type of clay materials and to provide information on the content of smectic components in the clay. From adsorption-desorption runs, data on equilibrium sorption of water in clay and on the sorption kinetics can be obtained.