I have only reviewed a handful of books before but I felt like this is one of those books that is actually helpful. If you have an intermediate knowledge of PHP and just want to go to the next level this book is great. I have a few years of experience and I gotta say this helped me bring my code to the next level in many ways. It is not a cook book or patterns book but it does cover some essential knowledge for any PHP professional. This will help you get to the next level of professorial if you have been writing code for a few years and want to rise above the general PHP hacker. Very good book. It could have been soft on content but the editors did a great job. Some people with more experience in PHP 4+ years might think this is a little soft but thats because they are close to the expert level. This book is for those who want to be expert and want to have not only a working knowledge of PHp but of the tools for good PHP coding. This book is not thin in content ans is a great resource.