Fantastic instructional book. Shows a lot of different core exercises. Exactly what part of the body they effect, modifications for the exercises. Starts with stretching, that I always forget to do. Goes through Swiss Ball, Body Weight, Free Weight and many other types of core exercise that you can do at home or in the gym.
I find it tough to find books like this, because you never know what exactly they show unless you actually go into the store to go through them or buy them and risk that they aren't what you are looking for.
I would totally buy this book. There's a yoga book coming out and I will definitely buy that one.