Essentially an expansion on the Player's Handbook, as the name implies. I love the imaginative new races, subclasses, feats, and spells presented in this book! I do think that a few of the races need minor rebalancing, but I haven't actually tried any of them in my games yet so I say that only from speculation, not from observation. Either way there are great ideas in this supplement and it is definitely worth the price!
[5 of 5 Stars!]