The drift mobility μ was measured in multilayer films consisting of alternating layers of an amorphous semiconductor and an insulator. The multilayer films contained up to 180 double layers with periods ranging from 48 Å to 180 Å. Plasma deposited hydrogenated amorphous silicon and silicon nitride were used for the semiconducting and insulating layers, respectively. We used the traveling wave technique in which the film to be measured is placed in the fringe electric field produced by a surface acoustic Rayleigh wave. The theory for the dc acousto-electric voltage drop V ae measured in the film plane was extended to multilayered films. V ae yields μ as well as the sign of the dominant charge carriers.