Method for automatically braking at least one trailer of a towing vehicle / trailer combination, wherein the towing vehicle has, as a service brake system, a friction brake, namely an electropneumatic friction brake system in the form of an electronically controlled brake system, and the trailer has an electropneumatic service brake system in the form of an electronically controlled brake system (TEBS), the method comprising at least the following steps: a) the monitoring of the at least one trailer by means of an electronic monitoring and control device as to whether the at least one trailer is being decelerated in the direction of travel, b) the monitoring of the friction brake system of the towing vehicle by means of the electronic monitoring and control device as to whether a brake request signal is being fed into the friction brake of the towing vehicle as a result of a brake request, wherein c) if no brake request signal is being fed into the friction brake system of the towing vehicle and if the detected deceleration (dV_rad/dt, a) of the at least one trailer exceeds a preset limit value, a trailer brake is activated automatically by means of the electronic monitoring and control device, and wherein d) the at least one trailer is monitored as to whether it is being decelerated by monitoring the signals of wheel speed sensors of the at least one trailer and/or by monitoring a longitudinal acceleration sensor of the trailer which senses in the direction of travel, and wherein e) the friction brake of the towing vehicle is monitored as to whether a brake request signal is being fed into a control unit of the friction brake system of the towing vehicle as a result of a brake request by means of monitoring the brake pressure of the at least one trailer, and/or wherein f) the friction brake of the towing vehicle is monitored as to whether a brake request signal is being fed into a control unit of the friction brake system of the towing vehicle as a result of a brake request by means of monitoring an electric brake control signal introduced into the trailer by the towing vehicle. a) the monitoring of the at least one trailer by means of an electronic monitoring and control device as to whether the at least one trailer is being decelerated in the direction of travel, b) the monitoring of the friction brake system of the towing vehicle by means of the electronic monitoring and control device as to whether a brake request signal is being fed into the friction brake of the towing vehicle as a result of a brake request, wherein c) if no brake request signal is being fed into the friction brake system of the towing vehicle and if the detected deceleration (dV_rad/dt, a) of the at least one trailer exceeds a preset limit value, a trailer brake is activated automatically by means of the electronic monitoring and control device, and wherein d) the at least one trailer is monitored as to whether it is being decelerated by monitoring the signals of wheel speed sensors of the at least one trailer and/or by monitoring a longitudinal acceleration sensor of the trailer which senses in the direction of travel, and wherein e) the friction brake of the towing vehicle is monitored as to whether a brake request signal is being fed into a control unit of the friction brake system of the towing vehicle as a result of a brake request by means of monitoring the brake pressure of the at least one trailer, and/or wherein f) the friction brake of the towing vehicle is monitored as to whether a brake request signal is being fed into a control unit of the friction brake system of the towing vehicle as a result of a brake request by means of monitoring an electric brake control signal introduced into the trailer by the towing vehicle.