Anchorage device, for use in anchoring objects to a track having a top channel opening defined between opposed overhanging channel lips, the anchorage device comprising: an elongate body having a front end, a rear end, an intermediate portion and an underside; plural track-engaging formations (3,4,5) attached relative to and distributed along the underside of the body, for insertion into the channel opening of the track in use and operable to provide a secured condition in which track-engaging formations are captive beneath the track lips and the anchorage device is held against being pulled out of the track, one or more of said track-engaging formations (4,5) being movable, in an actuating operation of the device, relative to one or more other said track-engaging formations and relative to the elongate body; the anchorage device further comprising an actuating mechanism for driving a said relative movement of one or more of said relatively movable track-engaging formations and an actuating member for driving the actuating mechanism, said actuating member being provided at the rear end of the body; the actuating mechanism comprising an elongate drive element extending longitudinally of the body, operatively connected at a proximal end thereof to the actuating member, and operatively connected at a distal part thereof to a said relatively movable track-engaging formation spaced along the body at a position longitudinally remote from said actuating member, whereby in said actuating operation, movement of the actuating member displaces the elongate drive element longitudinally to operate a said movement of said remote track-engaging formation longitudinally relative to one or more other said track-engaging formations, to provide said secured condition. an elongate body having a front end, a rear end, an intermediate portion and an underside; plural track-engaging formations (3,4,5) attached relative to and distributed along the underside of the body, for insertion into the channel opening of the track in use and operable to provide a secured condition in which track-engaging formations are captive beneath the track lips and the anchorage device is held against being pulled out of the track, one or more of said track-engaging formations (4,5) being movable, in an actuating operation of the device, relative to one or more other said track-engaging formations and relative to the elongate body; the anchorage device further comprising an actuating mechanism for driving a said relative movement of one or more of said relatively movable track-engaging formations and an actuating member for driving the actuating mechanism, said actuating member being provided at the rear end of the body; the actuating mechanism comprising an elongate drive element extending longitudinally of the body, operatively connected at a proximal end thereof to the actuating member, and operatively connected at a distal part thereof to a said relatively movable track-engaging formation spaced along the body at a position longitudinally remote from said actuating member, whereby in said actuating operation, movement of the actuating member displaces the elongate drive element longitudinally to operate a said movement of said remote track-engaging formation longitudinally relative to one or more other said track-engaging formations, to provide said secured condition.