Abstract: A stitching assembly for stitching together sheets of paper, card and similar materials comprises a frame carrying a number of stitching machines each of which includes a stitching head and a clinch block connected together so that each stitching head and its associated clinch block are movable along the frame as a unit. A code bar assembly which is mounted on the frame includes a number of code bars and co-operating means on the stitching machines and the code bars which co-operate to locate the stitching machines at positions along the frame determined by the spacing of the co-operating means along the code bar. The spacing of the co-operating means on each of the code bars is different and the code bar assembly includes means to move the code bars to enable each one of them to be associated with the co-operating means on the stitching machine.