A lumbar support assembly (2) comprises a support arrangement (3) which may have the form of a wire framework with two side wires (4) and a plurality of transverse wires (6). A Bowden cable arrangement (10) with a single Bowden cable is attached by two plate clips (15, 17) to the two side wires (4). A first end portion (13) of the wire (12) of the Bowden cable arrangement (10) is anchored to a front edge of a seat frame (1), while a second end portion (14) of the wire (12) is coupled to an actuator (20) for adjusting the tension of the Bowden cable. The lumbar support assembly (2) thus requires only one single Bowden cable to arch the lumbar support assembly at least in a lumbar region and to adjust the degree of lumbar support accordingly.