If you're a good Rails developer with experience, you won't lack for work nowadays (I am looking for people all the time it seems). This book has everything you need to become a good Rails developer. The experience bit is left as a reader exercise. The cute thing about this book is how it was developed. A few months ago it was released in a "beta" PDF form and sold to early adopters. The beta readers sent back lots of corrections, suggestions, and so forth.. and, wow, the book has undergone radical changes. It's precise, it's correct, and it's totally "canon" on the standards of developing in Ruby on Rails. It ought to be though, the developer of Rails is a co-author! I'm not going to go into what Rails is, or even what it does, as you shouldn't be here unless you know. If you need more information, go to the official Rails site which goes into it all in detail. But, this book is ace. You will not be wasting your money here if you want to be involved in the next massive thing in Web development. Put down your PHP books, and get involved in the exciting world of Rails.. your bank manager will thank you.