The invention relates to a brake system for motor vehicles having: an actuating unit (1) which comprises a brake booster (2) which can be actuated by means of a brake pedal (5) and can also be activated independently of the driver’s intention and a brake master cylinder (3) which is connected after the brake booster (2) and to which wheel brakes (13, 14, 15, 16) of a motor vehicle are connected, means (21) for detecting a driver’s retardation intention, a hydraulic control and regulating unit (HECU) (17) for carrying out dynamic movement control and regulating processes (ABS, ESP, ASR...) which is connected between the brake master cylinder (3) and the wheel brakes (13, 14, 15, 16) and has at least one hydraulic pump (24a, b), a first electronic control and regulating unit (7) which is assigned to the actuating unit (1) and serves to activate the brake booster (2), and a second electronic control and regulating unit (12) which is assigned to the hydraulic control and regulating unit (HECU) (17) and serves to activate the components. In order to make networking of the two electronic control and regulating units (7, 12) possible, it is proposed according to the invention that the first electronic control and regulating unit (7) has means (71, 72) which supply the second electronic control and regulating unit (17) with a setpoint value (pSoll) of the hydraulic pressure which can be set in the brake system, together with a request (St) for activating the hydraulic control and regulating unit (HECU) (17).