Grounded in the Saddle
Part 4: Yield the Hindquarters
The objective here is to have your horse move his hind end completely around his front end, stepping across with one hind foot in front of the other hind foot (disengagement). You and your horse should be very familiar with the ground-work version of this exercise before attempting it from the saddle.
It is easiest to start this exercise with forward motion, so begin by asking for a walk. Then bend your horse's head around to the right, as in One-Rein Stop, but put your right leg on him behind the girth, asking him to move his hindquarters to the left (away from your leg). At first you may have to bump him rhythmically with your heel until you get that all-important first step.
Once he has given you that first truly disengaged step, take your leg off of him and let him come to a stop. Give him his head (slacken the reins), and praise him. Repeat this and build on it until he will give you two to three disengaged steps in a row. Now change sides: bring his head around to the left, put your left leg on him behind the girth, and ask him to step his hindquarters around to the right.
You will probably find that he will pick this up more easily on one side then on the other. You will need to work a little longer on the sticky side to even him out. Remember to be patient, and build one or two steps at a time. Give him rest breaks, and praise him when he gets it right.