Abstract: A fall arrest device includes a U-shaped member (3, 5) adapted to accommodate a track (7) of a fall arrest system. A cam member (15, 17; 81, 83; 87, 89), including an actuating arm (21; 85) and a cam portion (19), is pivotably mounted on the device such that the cam portion is movable towards the U-shaped member so as to lock the track between the cam portion and an internal surface of the U-shaped member in the event of a fall. Biasing means (22) urges the cam member to a position in which the cam portion is adapted to allow the track to pass between the cam portion and the internal surface of the U-shaped member. Actuating means (27; 93) is adapted, in the event of a fall, to engage with the actuating arm or the cam member and to cause the cam member to pivot against the biasing force of the biasing means such that the cam portion locks the track.