An apparatus and a method are described for monitoring the activity of a driver of a vehicle, which apparatus has a device for monitoring several driver activities, by way of which various driver activities at the actuator for influencing vehicle motion are detected; and a device for evaluating the driver activity intensity level is provided, by way of which the intensity of the respective driver activity with regard to the urgency of the respective vehicle reaction is evaluated and is outputted as an intensity of the driver intervention; one of several different system reactions being selected depending on the intensity of the driver intervention, and the selected system reaction being executed.