One of a basic set of commands used by Shepherds when commanding sheep-herding dogs, (esp. Border Collies). Walk-on or Walk-up is used in the fetch and in the drive of the flock. Walk-On relays to the dog that the Shepherd wants it to walk straight to the flock and drive them away from the Shepherd or towards the Shepherd depending on the direction the dog is facing. (also see Sheep-herding commands)