Abstract: In a working chair with a seat (12), a back (14) and a lower frame the seat (12) is pivotally connected in the proximity of the front edge with a carrier frame (11) whereas a back support (15) connected with the back (14) is pivotally connected with the carrier frame (11) as well as with the seat (12). The pivot connections are provided for synchronous movement of the seat (12) and the back (14), whereby the seat from a backwards inclining extreme position may be moved to a forwards inclining extreme position and the back (14) synchronously therewith from a backwards inclining position in which it forms a maximum angle with the seat towards a more erect position, while gradually reducing its angle with the seat.