"I'll Be Missing You" is a song by American rapper Puff Daddy and American singer Faith Evans, featuring R&B group 112, in memory of fellow Bad Boy Records artist (and Evans's husband) 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 debut album, No Way Out (1997), "I'll Be Missing You" samples the Police's 1983 hit song "Every Breath You Take" with an interpolated chorus sung by Evans and interpolated rhythm. The song also interpolates the 1929 Albert E. Brumley hymn "I'll Fly Away" and features a spoken intro over a choral version of Samuel Barber's "Adagio for Strings".

At the 40th Annual Grammy Awards, the song won the Grammy Award for Best Rap Performance by a Duo or Group. The single spent eleven weeks atop the US Billboard Hot 100 and reached number one in 15 other countries; it was the best-performing single of 1997 in Iceland, the Netherlands (Dutch Top 40), and Romania. With shipments of over three million copies in the United States and over one million in both Germany and the United Kingdom, the song has become one of the best-selling singles of all time.

"I'll Be Missing You" is based on a sample of the 1983 single "Every Breath You Take" by the Police. It also uses an interpolation of the "Every Breath You Take" melody, sung by Biggie's widow, Faith Evans. Sean John Combs did not secure legal approval for the sample before releasing the song, and Police songwriter Sting sued, receiving 100% of the song royalties, with payments reportedly going until 2053.^[2][3] Police guitarist Andy Summers called the sample "a major rip-off", and told the A.V. Club: "I found out about it after it was on the radio ... I’d be walking round Tower Records, and the fucking thing would be playing over and over. It was very bizarre while it lasted."^[4] Sting later reconciled with Bad Boy, and performed the song alongside Puff Daddy and Evans in September 1997 at the MTV Video Music Awards.^[5][6]

The track also reuses the melody from the hymn “I'll Fly Away”.^[4] Combs's verses were actually composed by rapper Sauce Money.^[7] Combs had originally asked Jay-Z to write the track, but he turned it down and suggested that Sauce Money write the track instead.^[7]

Tom Sinclair from Entertainment Weekly panned the song, giving it a grade of D and describing it as a "maudlin 'tribute' to the Notorious B.I.G., [in which] the late rapper's former mentor (Puff Daddy) and wife (Faith Evans) team up to say their farewells to the big man on a song that 'samples' The Police's 'Every Breath You Take'. With lyrics like 'Know you're in heaven, smiling down/Watching us while we pray for you,' 'I'll Be Missing You' gives the lie to those who claim hip-hoppers are above self-serving sentimentality."^[8] British magazine Music Week rated it four out of five, calling it a "dignified tribute".^[9] Also James Hyman from RM gave the song four out of five, noting that "once again, blatant plundering from an Eighties groove forms the basis for an instant pop-rap crossover."^[10]

David Fricke from Rolling Stone wrote, "In "I'll Be Missing You", he didn't merely crib from Sting; he took a song about stalking and transformed it into a radiant hymn of brotherly love and a community's loss."^[11] Freelance music writer Jeremy Simmonds described it as "somewhat turgid".^[12] Ian Hyland from Sunday Mirror rated it nine out of ten, commenting, "Not the greatest rap I've ever heard but this tribute to murdered rapper Notorious B.I.G. is going to be H.U.G.E. In a mish-mash of The Police's "Every Breath You Take" and John Waite's "Missing", the highlight is Faith Evans' amazing voice."^[13]

"I'll Be Missing You" topped many charts across the world. It reached number one in the United States, the United Kingdom, Australia, Austria, Denmark, Flanders, Germany, Iceland, Ireland, Lithuania, the Netherlands, New Zealand, Norway, Poland, Romania, Spain, Sweden and Switzerland.

The song debuted at number one on the US Billboard Hot 100, and was the only rap song by a male artist to do so until Eminem's "Not Afraid" debuted at the top spot, thirteen years later, in 2010. The song spent a record-breaking 11 weeks at number one on the Hot 100, making it the longest-running number-one hip hop song in history, until Eminem's "Lose Yourself" spent 12 weeks at number-one in 2002.

The song re-entered the UK Singles Chart at number 32 on July 8, 2007, 10 years after it had its full physical release, and 10 years after it was number one. As of July 2013, "I'll Be Missing You" is the 22nd best-selling song of all time in the UK.^[14]

A music video was made to accompany the song, directed by American director Hype Williams and shot in Chicago. Portions of the video were filmed in the Helmut Jahn designed moving walkway tunnel that connects Concourses B and C in Terminal 1 at the O'Hare International Airport. The hill and motorcycle scene was shot at Sauer Family Prairie Kame Preserve in Elburn, Illinois. The music video was added to BET and MTV on the week ending on May 11, 1997.^[15]

• CD single

1. Puff Daddy featuring Faith Evans and 112 – "I'll Be Missing You"

• Maxi-single

1. Puff Daddy featuring Faith Evans and 112 – "I'll Be Missing You"
2. The Lox – "We'll Always Love Big Poppa"
3. 112 – "Cry On"
4. Puff Daddy and Faith Evans featuring 112 – "I'll Be Missing You" (Instrumental)
5. The Lox – "We'll Always Love Big Poppa" (Instrumental)