"Sing" is a song written by Take That singer-songwriter Gary Barlow and composer Andrew Lloyd Webber, and performed by a number of artists assembled by Barlow from across The Commonwealth, to commemorate the Diamond Jubilee of Queen Elizabeth II of the United Kingdom. The track was released via digital download and CD single on 28 May 2012, and was performed as part of the Queen's Diamond Jubilee Concert celebrations on 4 June 2012.

It was announced in January that six-time Ivor Novello recipient Gary Barlow and world-renowned composer Andrew Lloyd Webber would be working together to write the official Diamond Jubilee single. Barlow and Lloyd Webber aimed to write the music to the song before Barlow would travel The Commonwealth looking for musicians, singers and contributors and begin writing the lyrics and producing the song as he visited remote villages and countries from across the Caribbean, Africa, the Pacific Islands and Australasia to find singers to perform in front of the Queen. Barlow said of the project that "This is probably the biggest challenge I've ever taken on musically. I'm so excited and thrilled to be a part of it." Lloyd Webber echoed these views and stated that "It is a huge honour to be involved in this historic occasion and I am looking forward very much to working with Gary."

Barlow revealed that the music of the song was written in January during "an afternoon round at [Lloyd Webber's] house, [with a] couple of pianos and it was really good fun actually." He said that they "did all the melodies in an afternoon and then I waited to do the lyrics until I got to Kenya". Speaking about writing the track with Barlow, Lord Lloyd-Webber said: "We got together with embryonic ideas. Gary had an idea for the chorus, I had the idea for the verse, we both agreed that the message was about the Commonwealth. I was thinking 'anthem', but we had to involve all the people we could, and it had to be something very simple that people could learn. Working with Gary has been one of the great joys, he is such a fantastic songwriter, it was a completely new experience."

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