I was able to sit in a control room at the studio where the Beatles worked, doing my own mixes and isolating tracks, and I can honestly say I was surprised by everything I heard. Imagine what it was like for me, walking into Abbey Road Studios, opening tape boxes that had not been touched since they were shelved 20 years ago, and listening through professional equipment to the Beatles' recording-session tapes.

The book took years to research and compiles over 1,000 primary sources to provide an exhaustive guide. In 1986, Lewisohn published his first reference book, The Beatles Live!, a chronological guide of the group's live performances. Mark Lewisohn began formally researching the Beatles in the late 1970s, working as a research assistant for Philip Norman's book Shout! (1981). The project was nearly abandoned until Abbey Road employee Kathryn Varley pushed for its completion. Attendees were enthusiastic about the new information and suggested the catalogue be published, but Barrett's death in 1984 precluded it. In 1982, while attending Liverpool's annual Beatles convention, Townsend, Barrett and author Brian Southall used Barrett's work during a Q&A session. Barrett produced a colour-coded catalogue, which Townsend later said displayed an 'incredible' attention to detail.

Author Stephen Matteo alternatively suggests Barrett's work was intended to gather interesting unreleased material for The Beatles at Abbey Road, a 1983 multimedia presentation at Abbey Road Studios. Ken Townsend, the General Manager of Abbey Road Studios, later recalled suggesting Barrett keep his mind engaged by listening to the Beatles' session tapes and write down information pertaining to them. In the early 1980s, EMI balance engineer John Barrett found himself unoccupied while undergoing chemotherapy. The book has been widely described as an 'essential' reference book for study of the band. The book is written in the form of a diary, documenting each day from 1962 through 1970 that the Beatles spent in a recording session or producers and engineers spent mixing and editing their music. Hamlyn published it in the UK in 1988 and Harmony Books published it in the US. The Complete Beatles Recording Sessions (subtitled The Official Story of the Abbey Road Years 1962–1970) is a reference book on the English rock band the Beatles compiled by author Mark Lewisohn.

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