How does Clinton Anderson's sending exercise work and why is it important?

Clinton Anderson's Sending Exercise is one of the foundational exercises in his Downunder Horsemanship program, and it teaches the horse to move away from the handler with forward impulsion on direction — the ground equivalent of the leg aid that produces forward movement under saddle. The exercise is simple in concept but demands consistency in execution. The Sending Exercise involves directing the horse to move forward and away from the handler in a specific direction — typically around a barrel, fence post, or other object — by pointing in the direction of travel and applying rhythmic pressure from the stick if the horse does not move. The horse learns to move forward when pointed and to change direction when pointed the other way, all without the handler needing to chase or pull. Anderson teaches the Sending Exercise as a building block for several other exercises including trailer loading, leading through gates, and eventually yielding forward from leg aids. The key principle is that the horse is sent with energy — it should move forward willingly and at a reasonable pace rather than being reluctantly dragged. If the horse is sluggish, Anderson uses rhythmic pressure to create more forward energy. If the horse is charging through, he adjusts the exercise to include more direction changes that slow the feet. The Sending Exercise also establishes an important handler dynamic: the handler is directing the horse's movement without being in front of it or pulling it. The handler is behind the drive line, directing with energy. This is the same relationship that under-saddle work requires — the rider directs with leg and seat from behind, not by pulling from the front. Every repetition of the Sending Exercise on the ground is a repetition of this fundamental communication pattern. Anderson uses the Sending Exercise as a diagnostic tool: a horse that sends willingly in both directions, maintains its direction until asked to change, and returns softly when called in has the essential responsiveness to be ridden. A horse that doesn't is not ready.