British electronic production duo Chase & Status were always big fans of the Jamaican dancehall act Major Lazer, so when group's co-founder Diplo sent them an idea for a vocal, they jumped at the chance to test their skills in the moombahton genre (a fusion of house music and reggaeton). The actual vocal comes from another reggae artist, Ward 21's Andre "Suku" Gray. Will Kennard (Status) explained in a Spotify commentary: "The voice is just so incredible, it just jumps out, so we kept the track quite sparse and ended up not going down the kind of stupidly massive build-up, the humongous kind of drop which a lot of our songs sometimes have... just keeping it kind of cool and quite moody."
"Islands in the Stream" was originally written by The Bee Gees as an R&B song. It was originally written by the brothers for Marvin Gaye, however it was recorded instead as a duet by Kenny Rogers and Dolly Parton with the Gibb Brothers also contributing vocals.