Abstract: An apparatus for developing a latent image recorded on an imaging surface, comprising, a housing defining a chamber storing a supply of developer material; a donor member, spaced from the imaging surface, for transporting developer material on the surface thereof to a region opposed from the imaging surface, said donor member includes an electrode array on the outer surface thereof, said array including a plurality of spaced apart electrodes extending substantial across width of the surface of the donor member; means for loading developer material onto said donor member, a multi-phase voltage source operatively coupled to said electrode array, the phase being shifted with respect to each other such as to create an electrodynamic wave pattern having at a phase velocity for moving developer material to and from a development zone; and an AC voltage source operatively coupled to said electrode array, for applying an AC voltage in said development zone between the donor member and said imaging surface.