"I'll Be Missing You" is a song recorded by American rapper Puff Daddy and American singer Faith Evans, featuring R&B group 112, in memory of fellow Bad Boy Records artist Christopher "The Notorious B.I.G." Wallace, who was murdered on March 9, 1997.

Released as the second single from Puff Daddy and the Family's No Way Out album, "I'll Be Missing You" samples The Police's 1983 hit song "Every Breath You Take", with an interpolated chorus sung by Evans. The track also features a spoken intro over a choral version of Samuel Barber's "Adagio for Strings". In 1998, the song won the Grammy Award for Best Rap Performance by a Duo or Group. The single spent 11 weeks on top of the Billboard Hot 100 during the summer of 1997. With worldwide sales likely over 8 million, including shipments of 3 million copies in the United States and over 1 million in both Germany and the United Kingdom, the song has become one of the best-selling singles of all time. As of February 2016, it is rated the 99th biggest song of all time in the US, according to Billboard.

The song, a rap ballad, had already been completed before permission was granted to use the sample from The Police's "Every Breath You Take". Sting (vocalist from The Police) ultimately participated in a performance of "I'll Be Missing You" at the 1997 MTV Video Music Awards. Sting owns 100% of the publishing royalties. As well as using the melody and arrangement of "Every Breath You Take", the single also borrows the melody from the well-known American spiritual "I'll Fly Away".

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