In a Perfect World... is the debut studio album by American singer-songwriter Keri Hilson. It was released on March 24, 2009, through Zone 4, Mosley Music Group and Interscope Records. Originally planned for a 2007 release, it was pushed back numerous times into 2008, amid her label's budget issues and minor single releases. The production on the album was handled primarily by Timbaland, Polow da Don and Danja, among others.

"Knock You Down" is a song by American singer and songwriter Keri Hilson, recorded for her debut album, In a Perfect World.... The song features guest vocals from Ne-Yo and Kanye West. All three artists co-wrote the song with its producer Nate "Danja" Hills, as well as Kevin Cossom and Marcella Araica. The song was released first released to rhythmic and urban airplay in the United States as the album's fourth single in the US, and it would later serve as the third worldwide single.