A chair having an adjustable backrest and control actuator disposed forward of the backrest hinge, for controlling the backrest angle. The chair has a backrest support hinged to the backrest away from the backrest/chair hinge, and coupled directly or indirectly to track runners which run along elongated support tracks. A positioner is controlled by the control actuator and coupled to the backrest support and track runners, limiting the extent to which the track runners may move along the support tracks and thus control the angle of the backrest.