This research utilizes interferometer/polariscope equipment to obtain accurate results of the concentration and stress profiles (as a function of position and time) for penetrant transport in glassy polymers. The experimental studies will be carried out with divinyl benzene-crosslinked polystyrene samples exposed to cyclohexane at various temperatures. The effects of characteristic sample length, degree of crosslinking and transport temperature on the concentration and stress profiles will be investigated by the novel interferometric technique. These results will be used to verify a new mathematical model for liquid transport in glassy polymers. This model incorporates a generalized constitutive equation for the polymer in the diffusion equation. The final transport equation can be solved for a variety of boundary conditions. In its final form, it can be cast in terms of a characteristic diffusion and an average relaxation time. From the experimental results, one will be able to identify the conditions under which polymer relaxation becomes the controlling factor of the overall transport mechanism.