A support system for and method of supporting a printing screen unit in a screen printing machine. In one aspect the support system includes a support assembly comprising: a support unit far supporting a printing screen unit (3) comprising a printing screen (5) including printing apertures (6) through which printing medium is printed onto a workpiece; and a tensioning mechanism (18) for tensioning the printing screen in a screen printing operation, wherein the tensioning mechanism is configured to tension the printing screen to a first tension in a printing phase in printing printing medium onto a workpiece and a second tension, which is lower than the first tension, in a separation phase in separating the printing screen unit and the workpiece. In another aspect the support system includes a support assembly comprising: a support unlit for supporting a printing screen unit, the printing screen unit comprising a printing screen including printing apertures through which printing medium is printed onto a workpiece; and a clamping mechanism (27) for clamping the printing screen in a printing phase in printing printing medium onto a workpiece so as to fix the lateral, in-plane position of the printing screen.