"Sleepwalker" is a song by American recording artist and American Idol season eight runner-up Adam Lambert. The song was written by Ryan Tedder, Aimee Mayo and Chris Lindsey for Lambert's debut album, For Your Entertainment. It was released as a single in select countries. This song was written and recorded in 2009. It is the seventh and final single from the album on March 25, 2011. Germany was the only selected country where the single was released along with a music video; namely the live performance on the Glam Nation Live live album.

Song received positive reviews. Allmusic called this song "terrific pop" and added that it's "Tedder’s typically icy alienation." Entertainment Weekly was very positive "Lambert [gets] the chance to earn his power- ballad bona fides on the tense, atmospheric "Sleepwalker." However LA Times called this song "a real throwaway."

The song was included on the set list of Lambert's 2010 Glam Nation Tour. Lambert also performed the song on The Tonight Show with Jay Leno in late 2010.

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