"Who Is It" (sometimes "Who Is It (Carry My Joy on the Left, Carry My Pain on the Right)") is a song recorded by Icelandic singer Björk for her fifth studio album "Medúlla". It was released as the lead single from the album on 18 October 2004 by One Little Indian Records. Björk wrote "Who Is It" during the recording sessions for her previous album, "Vespertine" (2001), when it was known as "Embrace Fortress"; she left it off the album it as she felt it came from "a different family". The final version features throat singer Tanya Tagaq and beatboxer Rahzel, and lyrics reflecting the dialogue between mother and child.