Abstract: Disclosed are lowerable step assemblies as an accessory confined between the upright hinged-edge and free-edge of a door, and especially adapted for a motor vehicle door. The step assembly includes a step-on tread pivotably associated with the lower portion of a vertical rail guided by a track means aptly mounted at the door interior side, has an operative lower-station wherein the tread is horizontal and located in elevation between the opened door bottom-edge and an underlying substrate, and also has a stowed upper-station wherein the pivotal tread has automatically assumed vertical and parallel relationship to the closed door above the bottom-edge.