A control apparatus/method for operating an electromechanical brake booster of a vehicle braking system, including: applying control to an electromechanical brake booster motor in consideration at least of a braking definition signal regarding a braking input of a driver and/or automatic speed control system of the vehicle (ACC); specifying, in consideration at least of the braking definition signal, a target motor force of the electromechanical brake booster motor or a target brake application force of the electromechanical brake booster into a brake master cylinder, downstream from the electromechanical brake booster, of the braking system; and applying control to the electromechanical brake booster motor in consideration of a force difference between the specified target motor force and an estimated/measured actual motor force of the motor, or between the specified target brake application force and an estimated/measured actual brake application force of the electromechanical brake booster into the downstream brake master cylinder.