A coin operated lock assembly (30) is provided for attachment to a locker (12), the locker including a cabinet (14) and a door (16). The cabinet defines a locker loop (18) for locking the door using a padlock or the like. The coin operated lock assembly (30) includes a coin operated key lock mechanism including a locking plate (50) which is moved by operation of the key lock, wherein insertion of a coin in the lock allows the door to be locked and the key removed from the lock and wherein the locker is locked by means of a bolt (42) which is fixed to, or movable by, the locking plate (50) and which passes through the locker loop (18) of the locker when the assembly is attached to the locker door.