The study of double-stop octaves on the cello, for advanced cellists, continues in Octaves for the Cello, Book Four. Exercises and short pieces teach the octaves between the A, D, and high A hand positions learned in Octaves for the Cello, Book Three. Teachers can use this book to train their students in advanced double-stop playing on the cello before they are required to play octaves in solo literature, or as a technique supplement for students already playing octaves in cello literature. Professional-level cellists can use this book to refine and update their skills. This book can be followed by Octaves for the Cello, Book Five.