Abstract: A slipper guide for use in radial piston type hydraulic pumps and motors, especially those utilized in hydrostatic transmissions. The slipper guide provides an annular path for the slippers, guiding and maintaining the slippers engaged with the inner circumferential surface of the track ring as the slippers are rotated within the track ring by the cylinder. The slipper guide consists of two plates axially attached to the track ring and fixed relative thereto. Each plate includes an annular, axially inwardly extending projection forming an annular surface upon which an under surface of an outer portion of the slippers rests. The annular projection positions and maintains the top surface of the slippers against the inner circumferential surface of the track ring.