It developed from the aborted Lifehouse project, a multi-media rock opera conceived by the group's guitarist Pete Townshend as a follow-up to the band's 1969 album Tommy.

The project was cancelled owing to its complexity and to conflicts with Kit Lambert, the band's manager, but the group salvaged some of the songs, without the connecting story elements, to release as their next album.

The cover photo was shot by Ethan Russell; it made reference to the monolith in the 1968 film 2001: A Space Odyssey, as it featured the band standing by a concrete piling protruding from a slag heap in South Yorkshire, apparently having urinated against it.

[8] They had been touring since the release of Tommy the previous May, with a set that contained most of that album, but realised that millions had now seen their live performances, and Pete Townshend in particular recognised that they needed to do something new.

[16] The group held a press conference on 13 January 1971, explaining that they would be giving a series of concerts at the Young Vic theatre, where they would develop the fictional elements of the proposed film along with the audience.

[19] After returning to Britain, engineer Glyn Johns made safety copies of the Record Plant material, but decided it would be better to re-record the album from scratch at Olympic Sound Studios in Barnes.

[3] The group gave two more concerts at the Young Vic on 25 and 26 April, which were recorded on the Rolling Stones Mobile Studio by Andy Johns, but Townshend grew disillusioned with Lifehouse and further shows were cancelled.

[20] Audiences at the Young Vic gigs were not interested in interacting with the group to create new material, but simply wanted the Who to play "My Generation" and smash a guitar.

[20] The bulk of the sessions occurred during May, when the group recorded "Time Is Passing", "Pure and Easy", "Love Ain't for Keeping" (which had been reworked from a rock track into an acoustic arrangement), "Behind Blue Eyes", "The Song Is Over", "Let's See Action" and "Baba O'Riley".

[30] Despite Johns' key contributions, he only received an "associate producer" credit on the finished album,[23] though he maintained he acted mainly in an engineering capacity and based most of the arrangements on Townshend's original demos.

The song's title pays homage to Townshend's guru, Meher Baba, and minimalist composer Terry Riley, and it is informally known as "Teenage Wasteland", in reference to a line in the lyrics.

[29] The front cover of the album is a photograph, taken on 4 July 1971 on the way from Sheffield to Leicester, of the band apparently having just collectively urinated on a large concrete piling protruding from a slag heap.

[41] An alternative cover featuring Moon dressed in black lingerie and a brown wig and holding a whip was later used as part of the inside art of the 1995 and 2003 CD releases of the album.

[47] The set list was revamped, and, while it included a smaller selection of numbers from Tommy, several songs from the new album, such as "My Wife", "Baba O'Riley", and "Won't Get Fooled Again", became live favourites.

[48] The tour moved to the UK in September, including a show at The Oval in Kennington in front of 35,000 fans and the opening gig at the Rainbow Theatre in Finsbury Park, before going back to the US, ending in Seattle on 15 December.

[52] Reviewing for The Village Voice in 1971, music critic Robert Christgau called Who's Next "the best hard rock album in years" and said that, while their previous recordings were marred by a thin sound, the group now "achieves the same resonant immediacy in the studio that it does live".

[63] At the end of 1971, the record was voted the best album of the year in the Pazz & Jop, an annual poll of American critics published by The Village Voice.

[59] In a review for AllMusic, Stephen Thomas Erlewine said its music was more genuine than Tommy or the aborted Lifehouse project because "those were art – [Who's Next], even with its pretensions, is rock & roll.

"[54] BBC Music's Chris Roberts cited it as the band's best record and "one of those carved-in-stone landmarks that the rock canon doesn't allow you to bad-mouth.

"[65] Mojo claimed its sophisticated music and hook-laden songs featured innovative use of rock synthesizers that did not weaken the Who's characteristic "power-quartet attack".

[57] In The Encyclopedia of Popular Music (1998), Colin Larkin said the album raised the standards for both hard rock and the Who, whose "sense of dynamics" was highlighted by the contrast between their powerful playing and a counterpoint produced at times by acoustic guitars and synthesizer obbligatos.

[56] Christgau, on the other hand, was less enthusiastic about the record during the 1980s, when the Who became what he felt was "the worst kind of art-rock band", writing that Who's Next revealed itself to be less tasteful in retrospect because of Daltrey's histrionic singing and "all that synth noodling".