This book represents a way of thinking about jazz harmony. It explains how chords are built, named and used. It presents examples in the form of conventional notation, but also employs a novel method of illustration based on the image of the piano keyboard. A glossary of terms is included. If you need some kind of structure or framework of understanding to be able to do music at all, you may find it here. At the very least, by Step 20 you should be able to look at a chord chart and recognise (and even play) the symbols and patterns that form the foundations of the melodic theme, and improvisations based on it. The author is an experienced jazz pianist and has tested the lessons in this book over 50 years of self-education..