Experimental data obtained in the past several years have provided conclusive evidence that non-Bragg scattering plays a major role in X-band microwave backscatter from water wave surfaces, and non-Bragg scattering events are especially noticeable at small grazing angles, for wind-roughened surfaces, in the presence of breaking waves. We have conducted scattering experiments under a variety of wind wave conditions in an attempt to determine the different mechanisms which contribute to non-Bragg scattering. At small grazing angles we find that non-Bragg scattering is due to fast scatterers generated by the wave breaking, and with increasing wave steepness and surface roughness, mechanisms of multiple scattering and multipath interference become increasingly important. ¿ 1999 American Geophysical Union