Abstract: A self-adjusting single- or twin-tube shock absorber having a cylinder closed at both ends and filled with at least one damping medium, a piston rod sealingly inserted into the cylinder, and a piston carried on the cylinder side end of the piston rod for dividing a cylinder spaced into two half chambers. The piston rod has a longitudinal bore formed therein and at least one orifice traversing the longitudinal bore for connecting the two half chambers. An electrically controlled distributing slide valve device for opening and closing the orifice includes a slide valve sleeve coaxially surrounding the piston rod and the orifice and movable on the piston rod for opening and closing the orifice. A step motor has a slide valve as a movable part thereof for stepwise adjusting the slide valve and a stator including a plurality of exciter coils and coil formers surrounding the slide valve sleeve and the piston rod.