The Mathematics of poker by Bill Chen & some dude...

[Adman]

It is probably a great book but unless you have a strong math background you will find it frustrating. I know I was not able to get much out of it at all. I think the guys who are saying that it's "fairly basic" are much stronger in math than they realize. Also, I would add that I don't think understanding the complex material in that book is necessary to be a winning poker player, I'm sure it wouldn't hurt and could only help but certainly is not necessary.