Miles invites bebop pioneer Sonny Stitt to join his group, to replace John Coltrane. Jimmy Heath and Wayne Shorter had been his first choices, but Heath was on parole and could not leave Philadelphia, while Shorter was committed to Art Blakey’s Jazz Messengers. From 1960 to 1964, Miles brings a number of saxophonists into his group (Hank Mobley, George Coleman and Sam Rivers among them) but not until Shorter joins in 1964 does he seem satisfied.