Taking Back Sunday is an American rock band from Long Island, New York. The band was formed by guitarist Eddie Reyes in 1999.The band's members are Adam Lazzara (lead vocals), John Nolan (rhythm guitar, vocals), Eddie Reyes (lead guitar), Shaun Cooper (bass guitar, backing vocals) and Mark O'Connell (drums).

The band has released three studio albums with various past members Fred Mascherino (former lead guitarist and back-up vocalist), Matthew Rubano (former bassist), and Matthew Fazzi (former lead guitarist and back-up vocalist). The original Tell All Your Friends line-up reunited in 2010 and have released two studio albums: Taking Back Sunday and their most recent album Happiness Is.

Louder Now (2006) was the band's breakout mainstream album, notably because of the popularity of its lead single "MakeDamnSure." The album has sold over 900,000 copies and peaked at No. 2 on the United States Billboard 200, surpassing the band's previous Billboard 200 peak in 2004 at No. 3 with Where You Want to Be. Before the release of their first studio album Tell All Your Friends (2002), they had released Taking Back Sunday's EP in 2001, when the band featured former lead vocalist Antonio Longo. At that time the EP received very little attention, eventually resulting in the band seeking a new lead singer in, Adam Lazzara, who had at first joined the band as guitarist then leaving a few months after forming, replaced original bassist Jesse Lacey (now of Brand New) during the EP's recording sessions.

John Nolan and Shaun Cooper previously left the band in 2003 only to rejoin in 2010, in time for the band's release of their eponymous album Taking Back Sunday on June 28, 2011. The album was produced by Eric Valentine and released through Warner Bros. Records.