A brake device having a hydraulic booster stage for a hydraulic motor vehicle brake system is provided, which brake device, within normal boosting operation, can be operated both in an autonomous, driver-independent actuation mode with electronic control and in a manual actuation mode controlled by the driver, and outside normal boosting operation, can be operated in an emergency mode with a non-boosted actuation force generated by the driver alone, in the case of which brake device it is proposed that, within normal boosting operation, each actuation mode is assigned a dedicated piston in a booster housing of the booster stage, which piston is acted on directly with the boosting force and transmits this mechanically to components connected functionally downstream.