"If You Leave Me Now" is the title of a popular hit ballad by the American rock group Chicago, from their album Chicago X. It was written and sung by bass guitar player Peter Cetera and released as a single on July 31, 1976.

It is also the title of a compilation album released by Columbia Records (Columbia 38590) in 1983.

The single topped the US charts on October 23, 1976, and stayed there for two weeks, making it the first number one hit for the group as well as hitting number one on the Easy Listening charts. It also reached number one in the UK on November 13, 1976, maintaining the position for three weeks.

"If You Leave Me Now" was also Chicago's biggest hit worldwide, topping the charts in other countries such as Australia. It won Grammy Awards for Best Arrangement Accompanying Vocalist(s) (strings) for arranger Jimmie Haskell and producer James William Guercio and Best Pop Vocal Performance by a Duo, Group or Chorus. It also received a nomination for Record of the Year. In addition, by August 1978 it had sold 1.4 million copies in the United States alone. It has been certified gold and platinum by the RIAA.

The song has been featured in several television series and movies such as Three Kings, Shaun of the Dead, A Lot Like Love, Sex and the City, Happy Feet, South Park, and the video game Grand Theft Auto V.

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