The leg-yield is one of the first lateral exercises to be introduced to a horse, teaching it a simple yet valuable lesson: to move sideways away from leg pressure.
Improper execution of the leg-yield can have a negative effect on a horse's training, causing loss of forwardness, resulting in short, broken gaits.
The Spanish Riding School uses this exercise sparingly, and only at the walk, when first teaching the horse to move away from the leg.
Because the horse will be bent in the opposite direction learning the more difficult half-pass, it is believed to be counterproductive to spend much time on the leg-yield.
The most common place the leg-yield is performed is from quarter line to rail, keeping the horse's body parallel to the wall.