I just went to see a new counselor and he recommended that I read it. I've been suffering from depression episodes for years now.
It's a very interesting book, and I recommend it to anyone who suffers from depression, even if it's just occasional.
I took the first test in the book and scored average to very pessimistic (there are different categories that are tested). Being pessimistic can have a direct correlation to depression. Here is the book on Amazon:
http://www.amazon.com/exec/obidos/tg/detail/-/0671019112/qid=1129644988/sr=8-16/ref=sr_8_xs_ap_i1_xgl14/103-9190678-6267816?v=glance&s=books&n=507846