Movement agents are responsible for coordinating the movements of trains. On a single-track line, this function is essential for the safety of all. It is he who will give to the chief train (chief guard) the information that the track is free.

The leader of the movement probably fulfills one of the most obscure functions of the exploitation. His task, however, is among all the most important. The leader of the movement is also responsible for organizing traffic (schedules, special trains, etc.)