This book is very clear, very clean, and I agree, a must on the subject. It is accompanied by practical exercises that allow to get into the thick of it, and have the enormous merit of being very simple, effective and rewarding (at least in my case). I loose more. It may be accompanied most advantageously drum that the author has recorded CDs and are designed to accompany the exercises of the book (eg, Vol. 1-Sham Jrny Solo & Dbl). I really enjoyed myself to associate the two.