"One Perfect Day" is a song written by Phillip Buckle, David Hobson, and Paul van Dyk and recorded by Australian singer Lydia Denker as the theme to the 2004 film One Perfect Day (2004). Produced by Sam Melamed, the song is a pop rock love song. It was released as a CD single and maxi single on 16 February 2004 (see 2004 in music) and was the only song released from the soundtrack.