In 1964 he co-wrote A Cellarful of Noise, the autobiography of the Beatles' manager Brian Epstein. Soon after, he became Epstein's personal assistant and Beatles press agent. In 1965 he moved to Los Angeles and started his own public relations company, managing the PR for bands like Paul Revere and the Raiders, the Byrds and the Beach Boys. He was also a co-creator and producer of the historic Monterey Pop Festival in 1967. A year later, he returned to England to work for the Beatles again as the press officer for the newly created Apple Corps.