A model was developed to predict the drying behavior of multilayer polymer films on inert substrates. The model considers simultaneous heat and mass transfer controlled by complex thermodynamic and transport properties of polymer solutions. Key components of the model are the incorporation of the free volume theory to predict diffusivities in each polymer layer, the use of heat and mass transfer coefficients to describe complex transport phenomena in the gas phase, the incorporation of exact equilibrium boundary conditions at polymer-polymer interface, and the use of the Flory-Huggins theory to describe both liquid-liquid and vapor-liquid equilibria. The model can be applied to guide processing, product formulation, scale-up, and oven design. As an example, the model is applied to simulate the drying of a two-layer coating of poly vinyl acetate tin toluene) over polystyrene (also in toluene) on a polyester substrate.