Very solid introduction to chess, introducing the key concepts of all three phases and providing a solid base for learning and applying strategy and tactics. It contains a full glossary and reference of terms in the the appendices, making it a decent reference as well, although the format of the book, framing each chapter as a lesson, written in conversation form between a teacher and student, can make locating a reference point difficult - I recommend NM Pandolfini's Weapons Of Chess to better serve this purpose.
An interesting point to note: this book is very similar to another of NM Pandolfini's works, the now out-of-print Principles of the New Chess - in fact, as cited in the appendices, some passages, at least two that I recognized, are lifted word for word from that work. The example game is very similar as well, though I haven't compared them side-by-side to see if they are the same. The difference in format is the most obvious: Principles is written in a standard style, addressing the reader, whereas the Ultimate Guide is written as a conversation. In many way, the newer book is an updated, rewritten, and much expanded version of Principles, though it doesn't advertise itself as such. Be aware that you only really need one of these books, and that the Ultimate Guide is much superior.