Turn on the forehand is a lateral movement in equestrian schooling that involves moving the horse's hindquarters around his front legs.
During the turn, the horse's forehand should be prevented from moving forwards, sideways or backwards.
If the horse understands the leg-yield, a review of that movement can be helpful in reminding him to move away from leg pressure, before he begins the turn on the forehand.
When asking for the turn on the forehand, the inside and outside aids switch in relation to the new direction of the bend.
The movement can be beneficial to the horse, in that it improves form and encourages stretching and flexion of the inside hind leg.