"Us and Them" is a song by the English progressive rock band Pink Floyd, from their 1973 album The Dark Side of the Moon. The music was written by Roger Waters and Richard Wright with lyrics by Waters. It is sung by David Gilmour, with harmonies by Wright. The song is 7 minutes, 51 seconds in length, making it the longest on the album.

"Us and Them" was released as the second single from The Dark Side of the Moon in the United States, peaking at No. 72 on the Cash Box Top 100 Singles chart in March 1974. The single peaked at No. 85 in the Canadian chart.

"Us and Them" is rather quiet in tone and dynamics, with prominent jazz influence, although the choruses are louder than the verses. It has two saxophone solos in it, one at the beginning and another towards the end of the song. Richard Wright introduces the song with harmonies on his Hammond organ, and put a piano chordal backing and short piano solo afterwards on the arrangement. The tune was originally written on the piano by Wright for the film Zabriskie Point in 1969 and was titled "The Violent Sequence". In its original demo form it was instrumental, featuring only piano and bass. Director Michelangelo Antonioni rejected it on the grounds that it was too unlike material such as "Careful with That Axe, Eugene", which was the style of music he wanted to use. As Roger Waters recalls it in impersonation, Antonioni's response was: "It's beautiful, but is it too sad, you know? It makes me think of church". The song was shelved until The Dark Side of the Moon, where Waters put some lyrics to it.

The verses have a unique, jazz-influenced chord progression: Dsus2, D6add9 (or Esus2/D), D minor major 7, and G/D. The tonic of D, alternating with the dominant, A, is sustained on bass guitar as a pedal point throughout the verses. The D6 with an added 9th is not unlike an Esus2 with a D in the bass, but because the bass line also provides the fifth, it is more accurately described as a kind of D chord. The D minor chord with a major seventh is a rarity in 1970s rock music. There is also a secondary sequence, louder, with thick vocal harmonies, with a progression of B minor, A major, G major seventh suspended second, commonly written as "Gmaj7sus2" (enharmonic to the slash chord D/G), and C major. This progression is played twice between each verse, and is not unlike a chorus, except that the lyrics are different with each repeat.

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