"Shine On You Crazy Diamond" is a nine-part Pink Floyd composition written by Roger Waters, Richard Wright, and David Gilmour. The song is a tribute to former band member Syd Barrett, although it was not originally explicitly written with him in mind. It was first performed on their 1974 French tour. It was recorded for the 1975 concept album Wish You Were Here. The song was intended to be a side-long composition like "Atom Heart Mother" and "Echoes", but was ultimately split into two parts and used to bookend the album.
According to David Gilmour and Nick Mason on the Wish You Were Here episode of In the Studio with Redbeard, the band recorded a satisfactory take of "Shine On You Crazy Diamond", but because of a new mixing console which was installed at Abbey Road, it needed to be re-recorded because excessive 'bleed' from other instruments could be heard on the drum tracks.
In another incident, Syd Barrett wandered into the studio (heavyset, with a completely shaved head and eyebrows) while the band was recording Wish You Were Here, although Nick Mason has since stated that he's not entirely certain whether "Shine On You Crazy Diamond" was the particular song being recorded when...