The valve piston (2) guided within the valve body (1) is pressed into the valve seat (3) by the hydraulic power and the spring force (7) generated by the operating pressure (P) on the control surface (6). Thus, the line (P) is shut off and the lines (A, T) are connected. By switching the pilot valve (5), the control surface (8) is pressurised and the valve piston (2) is moved into the actuated position. Thus, the valve piston (2) is pressed into the valve seat (4), the lines (P, A) are connected and the line (T) shut off. Within the switching phase, the valve is provided with a positive overlap.