First of all, I think it's between 3 and 4 actually. Good parts: it has some useful information like caching support, explanations of inner workings of persistence context, and it was just good to read it through because there are always some parts missing when you don't read everything or just make every single mistake with a framework, and Hibernate has a lot of complexity to it. I also think most of the people using it are just looking recipes up on the internet or reading tidbits of documentation. Well, that was what I did, anyway reading this book gave more structure to my knowledge of Hibernate. Bad parts: it's just hard to read it through! And you probably shouldn't. There are lots and lots of stuff which is relevant to only small percentage of users in my opinion. Also my opinion, I don't think that it's worthwhile to include such stuff in a book, I think doc reference is good enough to that end. (And Hibernate docs are like really good.) Reading some chapters, and skipping not interesting/relevant things recommended to anyone working with Hibernate (well, or documentation).