Abstract: A vehicle seat has a back-rest (1) carrying a head-rest (2). A mechanism is provided to move the head-rest (2) forwardly relative to the back-rest (1) in response to a rear impact situation. An element (9) is operatively located between the head-rest (2) and the mechanism (6) which is adapted to yield when exposed to a force in excess of a predetermined force. Thus the force that can be applied by the head-rest (2) to a head (8) of an occupant of the seat, is limited to be a maximum of 200 Newtons, with the preferred value being 100 Newtons.