Abstract: An apparatus for reciprocating an infant support comprises a frame and a receiving member supported above the frame for substantially vertical reciprocating movement. The receiving member is configured to receive the infant support and, in one embodiment, is coupled to the frame by a reciprocating assembly configured to constrain the motion of the receiving member in a substantially vertical direction. A motive device coupled to the receiving member reciprocates the receiving member relative to the frame. The apparatus may also include a counterbalance mechanism configured to offset the load of the infant and the infant support on the motive device.