Abstract: A press operating with hydraulic pressure comprises a pair of relatively movable components (8, 11) which during a pressing operation carry out a relative movement which is sensed. By use of the sensed relative movement a control signal is generated which is used for regulating the hydraulic pressure so that this is caused to vary with the relative movement according to a certain functional relationship. For generating the control signal a manually programmable electrical function generator (23) is provided, preferably a panel (29) comprising plug contacts (34), on which a plurality of pairwise associated pressure and movement values, constituting electrically and visually readable points in the desired functional relationship, can be set up.