The invention relates to a brake device and a hydraulic device for motor vehicles, comprising at least two hydraulic brake circuits (1, 2), which are directly connected to a master brake cylinder (9), and comprising a further brake circuit (3), which can be actuated via a control unit (22) independently from the master brake cylinder. Due to the separate hydraulic brake circuits (1, 2) in the region of the front axle, the required redundancy is provided, while the third brake circuit (3), which can be actuated independently of the master brake cylinder and typically acts on the rear wheels, during automatic actuation allows the consideration of a braking effect by additional units (20), such as a driven generator.