A simple model for the near-bottom combined wave and current flow over a moveable sediment bed is presented. The model is an extension of the Grant andMadsen (1979) combined wave and current model, with moveable bed effects on the physical bottom roughness included as by Grant and Madsen (1982). The unsteady conservation of fluid momentum and sediment mass equations, which are coupled through an eddy diffusivity closure scheme, are solved for the wave and current velocity profiles, along with the suspended sediment concentration and transport profiles. Sample runs are presented to illustrate the effect of varying wave conditions on the current, the mean sediment concentration, and the mean sediment transport. Results show that for fine to medium sands, self-stratification of the flow can be important during storms owing to the large amount of sediment suspended by the waves and the enhanced turbulent mixing associated with the wave-current interaction. The theory easily can be generalized for inclusion in a full Ekman layer model. ¿ American Geophysical Union 1987