Abstract: A hydraulic brake system with anti-lock control and traction slip control has an electric-motor-driven hydraulic pump 6 and a motor 7 for auxiliary pressure supply during a controlled braking operation and during a traction slip control operation by way of brake management. During a traction slip control operation the speed of the hydraulic pump is reduced by way of a reduction in the power consumption of the drive motor of the pump down to a predetermined value where the speed and the noise development are low relative to values with nominal capacity. The power limitation will be cancelled in situations critical to safety and reliability or in case of certain malfunctions of the control system. The power limitation is achieved by way of relays and an ohmic series resistor or by way of a so-called semiconductor relay or electronic relay.