Abstract: An apparatus is provided for adjusting the position of a backrest relative to a chair seat. The backrest includes an elongated stem having a curved lower portion. Preferably, a spring operably engages the stem to bias it in an upward direction. A housing is adapted to slidably receive the curved portion of the stem and guide the spring. A latch mechanism is adapted to engage the stem to lock the backrest in a desired position, and an actuator member is adapted to move the latch mechanism between an engaged and disengaged position. In operation, the latch mechanism is disengaged to allow the backrest stem to move in a curvilinear path to a desired height and corresponding angular position, and reengaged to lock the backrest stem in said position.