Focus
These exercises create a relationship that requires the person and the horse to pay close attention to each other. If you have a round pen great. These can be done anywhere. You need to make sure your horse respects your space, and leads up free before beginning these exercises.
I first do a little exercise, going around, and limbering up the horse, asking the horse to pay attention to me. Then I start 1/2 circles. This means, you will change the direction the horse is traveling when he reaches either the left or right side of you.
In other words the horse will never travel behind your back. Some look at this as a figure 8, I prefer the horse does a "D" on each side. You are working both sides at one time. When the horse becomes comfortable with this maneuver, I begin to make this exercise more aggressive. The turns at the end of the crossover become more of a roll back.