Abstract: The cushion has a contoured base with a layer of resilient cushion foam thereover. The cushion foam is of uniform thickness over a substantial part of the base and is suitably covered. The shape is such that the buttocks of the seated person are clasped positioned rather than supported. A recess is provided under the ischia, under the trochanters, and beneath the sciatic nerves to limit the local pressure. In one configuration, these recesses may contain air bladders which are inflated by body motion against a back bladder in the cushion. In another embodiment, the various bladders may be sequentially pressurized to shift the bearing areas under the buttocks of the seated user in order to periodically lift the user for stimulating blood circulation.