Vespertine is the fourth studio album by Icelandic recording artist Björk. It was released on 27 August 2001 in the United Kingdom by One Little Indian Records and in the United States by Elektra Entertainment. Björk aspired to create an album with minimal and intricate electronic music to evoke an intimate and domestic feeling, in contrast with the louder styles of her previous studio album Homogenic (1997). She enlisted producers such as Opiate, Console and the duo Matmos, and has also worked with harpist Zeena Parkins. Production on the album began whilst filming her role in Dancer in the Dark.

"Cocoon" is a song by Icelandic singer Björk for her fourth studio album, Vespertine (2001). Written and produced by Björk and Thomas Knak, it was released as the album's third single on 11 March 2002 by One Little Indian Records. Inspired by her relationship with artist Matthew Barney, Björk wanted to create a record with a domestic mood. Working with Knak, she wrote "Cocoon", a song which is lyrically about a woman who describes making love with her lover during their post-coital hibernation, and includes frank sexual narrative related both explicitly and through over-sharing and metaphor.