Piston-cylinder assembly, in particular gas spring, comprising a cylinder as a first structural unit, in which a piston rod is arranged in an axially movable manner as a second structural unit. An adjusting device exerting an adjusting force includes an acturator and a force-transmitting means operatively connected to the piston-cylinder assembly, the force-transmitting means engaging concentrically on one of the two structural units of the piston-cylinder assembly.