One of a basic set of commands used by Shepherds when commanding sheep-herding dogs, (esp. Border Collies). A command that redirects the dog's attention from the flock to missing sheep that have fallen out-of-sight. In trials, the dog is required to split the flock in two and drive twenty sheep to the pen. The Shepherd then gives the Look Back command, instructing to the dog to run back to the pasture to drive the rest of the flock. (also see Sheep-herding commands)