Abstract: A brake actuation device for a vehicle trailer including a mounting for mounting relative to the trailer, an actuator arranged to be coupled to a braking system of the trailer and movable to actuate the braking system, a movement driver for driving movement of the actuator, a sensor for sensing a predetermined condition, and a controller in communication with the sensor and arranged to operate the movement driver in response to the sensor detecting the predetermined condition, wherein the device has a locked condition in which the actuator is mechanically locked in position.