Abstract: A chair back is disclosed and includes a mesh material connected to a two-piece carrier, the carrier being deformable and stretchable. The carrier has a bottom edge including a groove and is engageable by tabs attached to a transverse member of a chair frame assembly. The upper ends of the carrier each includes an opening for receiving a spherical end portion of the upper end of the chair frame assembly. Engagement of the carrier with the chair frame assembly is accomplished by stretching the carrier and mesh between the transverse member and the spherical end portions. The chair back includes a lumbar support which is mounted to slide along the side edges of the carrier and along vertical supports of the chair frame assembly, the lumbar support causing the chair to tension forwardly. The chair back is pivotal under the influence of a chair user and is pivotally connected to the chair seat so as to cause the chair seat to also pivot in response.