A valve has a control slide (4) guided in a valve housing (6) so as to be longitudinally movable. The control slide selectively connects a plurality of fluid connection points (P, T, A, B) in the valve housing (6) to each other in a fluid-conducting manner or disconnects the fluid connection points from each other, and can be electrically controlled by a stepper motor (2). The control slide (4) can be actuated by an emergency device (34, 52) in the event of a malfunction or failure.