A chair having an adjustable resilient back recliner mechanism, a pair of adjustable armrests, modular upper back portions and an adjustable lumbar support. The chair includes a tension control that adjusts the tension in the recliner mechanism. The tension control is cam-operated to permit adjustment throughout the entire range of adjustability with only limited rotational movement of a control knob. The chair includes a recline limit control that adjusts the limit of rearward movement in the recliner mechanism. The limit control includes a cable operated stop that interact with a stepped trackway on the seat. The chair further includes a height control for adjusting the seat height including a push-button located in the tension control knob. The armrests include height and angle adjustment mechanisms. The lumbar support includes a lumbar cam that is rotatably mounted to a lumbar pad. The lumbar cam includes a plurality of lobes that vary in radius so that rotation of the cam causes variation in the contour of the lumbar region. The chair back includes a fabric carrier with an upper back portion mounting platform that permits attachment of any of a variety of modular upper back portions.