A chair of the type commonly found in a home or office and having a stationary back, a pair of arms, and a rotatable seat cradle that is located between the arms. The seat cradle includes a lumbar portion lying against the stationary chair back to support the user's lower back and a seat cushion portion to support the user's pelvis. The lumbar portion and the seat cushion portion of the seat cradle are connected to one another so as to rotate together as a unit relative to the stationary back and the arms of the chair. By virtue of the foregoing, the hips and spine of the user will be continuously aligned whenever the user shifts his weight in the chair, whereby to maximize user comfort and improve user posture.