The biography of the musical collaboration "Brandy and Monica" primarily centers around their iconic 1998 duet "The Boy Is Mine." This song, a mid-tempo R&B track inspired by Michael Jackson and Paul McCartney's "The Girl Is Mine," features lyrics about two women competing for the affection of a man. It was co-written by Brandy Norwood, Rodney "Darkchild" Jerkins, and others, and produced by Jerkins and Dallas Austin. Released as the lead single from both Brandy's album "Never Say Never" and Monica's album "The Boy Is Mine," the song capitalized on media-fueled rumors of a rivalry between the two singers, which they both denied.

"The Boy Is Mine" achieved significant commercial success, becoming the best-selling song of 1998 in the U.S. and spending 13 weeks at the top of the Billboard Hot 100. It also topped charts internationally, including in Canada, the Netherlands, and New Zealand. The accompanying music video, directed by Joseph Kahn and featuring Mekhi Phifer, was nominated for two MTV Video Music Awards. The song earned Brandy and Monica a Grammy Award for Best R&B Vocal Performance by a Duo or Group and received nominations for Record of the Year and Best R&B Song.

Despite rumors of a feud, Brandy and Monica later collaborated on the 2012 single "It All Belongs to Me" and participated in a remix of Ariana Grande's 2024 single "The Boy Is Mine." Their professional relationship, marked by both collaboration and media speculation, remains a notable chapter in the history of R&B music.