A self-propelled monitoring device for autonomously patrolling a region includes a drive unit, a power supply system, at least one sensor for detecting a surrounding area, a control unit for evaluating data supplied by the sensor and for ascertaining an action to be carried out next, and a signal generating device. An image of the surrounding area is captured by the at least one sensor, and the sensor image is analyzed by the control unit. The position of a person present in the surrounding area is ascertained, and a signal which is directed towards the ascertained position is output by the signal generating device.