A method for operating vehicles, in particular track-bound vehicles, permits two vehicles to approach one another even to comparatively short distances and at the same time can be implemented with comparatively low expenditure. For this purpose, a collision by a first vehicle towards the rear of a second vehicle is detected by the second vehicle, a warning message is emitted by the second vehicle triggered by the detection of the collision or running into from the rear, and a braking process is triggered by the first vehicle on the basis of the warning message emitted by the second vehicle. A device for a vehicle which detects the collision of a further vehicle is also provided.