"Shine On You Crazy Diamond" is a nine-part composition recorded by English rock band Pink Floyd written by David Gilmour, Roger Waters, and Richard Wright, which was first performed on their 1974 French tour and appeared in their 1975 concept album Wish You Were Here.

The song is written about and dedicated to founding member Syd Barrett, who departed from the band in 1968 after dealing with mental health problems and substance abuse.

The song originated from a riff composed by Pink Floyd guitarist David Gilmour and was later developed by him, bassist Roger Waters and pianist Richard Wright.

The track was originally 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, with other newly composed material acting as a bridge.

[10] According to guitarist David Gilmour and drummer Nick Mason on the Wish You Were Here episode of In the Studio with Redbeard, Pink Floyd recorded a satisfactory take of "Shine On You Crazy Diamond" but because of a new mixing console which was installed at Abbey Road Studios, it needed to be re-recorded as excessive 'bleed' from other instruments could be heard on the drum tracks.

That part was re-recorded at British Grove Studios by pianist Richard Wright during the multi-channel mix used for the album Immersion Edition and the SACD release.

The sequence was recorded on 5 January 1971, originally intended to be a part of a series of musical experiments the band conducted titled "Nothings".

[14] On 5 June 1975, Barrett, by this point heavyset, with a completely shaved head and eyebrows, wandered into the studio where the band were recording.

I thought, "He looks a bit... strange..." Anyway, so I sat down with Roger at the desk and we worked for about ten minutes, and this guy kept on getting up and brushing his teeth and then sitting – doing really weird things, but keeping quiet.

The instrumental begins with a fade-in of a G minor chord created with an EMS VCS 3, ARP Solina string synthesizer, a Hammond organ, and a wine glass harp (recycled from an earlier project known as Household Objects).

This is followed by Wright's Minimoog passages leading into a lengthy, bluesy guitar solo played by Gilmour on a Fender Stratocaster (neck pickup) using a heavily compressed sound and reverb.

This solo is often dropped in live performances while the rest of part III is still played—notably on Delicate Sound of Thunder and Pulse.

Then Wright comes in playing a Solina String Ensemble Synthesizer and after a few measures, several rhythm guitar parts (Gilmour played the power chord rhythm part using his black Fender Stratocaster before switching to lap steel guitar for the solo in live performances from 1974 to 1977.

Snowy White performed the rhythm guitar parts on this track on the band's 1977 In the Flesh Tour) and drums come in, as well as a Minimoog to play the opening solo.

The song then switches time signatures to 68 (found in Parts II–V), giving the appearance of a slower tempo and reintroducing the vocals.

In addition to their guitar solos, there was also occasional trading of leads from Gilmour and White instead of the keyboard sounds as heard on the record.

On the fade-out, a short keyboard part of the melody of "See Emily Play" (at 12:07), one of Barrett's signature Pink Floyd songs, can be heard.

When performed early on the Animals tour, the part begins with the piano (as heard on the record) then the synth solo is played (as on the record) by Dick Parry with some slide guitar accompaniment by Snowy White would then change to half synthesizer/half harmony lead guitar solo for the remainder of European leg and first US leg.

The multi-part version of "Shine On You Crazy Diamond" was first performed on the band's 1975 North American tour with "Have a Cigar" in between the two halves of the piece.

The band performed the whole nine-part "Shine On You Crazy Diamond" as part of the Wish You Were Here portion of their 1977 In the Flesh Tour, with extra musicians White on guitar and backing vocals and Parry on saxophones and additional keyboards.

The track (without the Gilmour solo in part III) opened shows for most of the A Momentary Lapse of Reason Tour, including its final performance at Knebworth in 1990 with Candy Dulfer on saxophone.

[26] The first eleven performances had "Echoes" as the show opener before the band proceeded to play all of A Momentary Lapse of Reason in the rest of the first half in a slightly different sequence to the album.

In many of his performances, solo and with Pink Floyd, Gilmour alters the vocal melody to avoid the higher notes that were originally sung by Waters.

Waters has also performed the epic on his In The Flesh concert series, documented on the live album of the same name which was a condensed parts I, II, IV, VI, VII, and VIII.