"I'm Not Alone" is the lead single from Scottish DJ and producer Calvin Harris' second album, Ready for the Weekend, and his first appearance on a single since "Dance Wiv Me" with Dizzee Rascal and Chrome, which peaked at number 1 in the UK singles chart in 2008. "I'm Not Alone" was first-played by Pete Tong on BBC Radio 1 as his "essential new tune" on January 23, 2009 and has been described as a slice of euphoric dance. On April 12, 2009, the song debuted at #1 on the UK Singles Chart, giving Harris his first solo #1 single in the UK and second overall.