The invention relates to a positively engaging shifting element which can be hydraulically or pneumatically actuated, comprising a hydraulically or pneumatically actuatable piston (I) having a piston compartment (2) containing a hydraulic medium or pressure medium, a jaw (3) having a dog-type gearing (4) and a mating jaw (5) with which the dog-type gearing (4) meshes when engaged. The engaging speed of the jaw (3) can be increased by decoupling the jaw (3) from the hydraulic or pneumatic volume flow when the jaws (3) and (5) are in a tooth butt position in relation to each other and by pretensioning the jaw (3) by means of a mechanical device (6) that is actively connected to the piston (I). The gap between the jaws, i.e. the window into which the jaw (3) can be engaged is maintained as narrow as possible in order for a tooth butt position of the jaws (3) and (5) in relation to each other being highly probable when the shift element is applied.