All-4-One is a male R&B group best known for their hit single "I Swear" from their self-titled 1994 debut album.

"I Swear," a remake of the John Michael Montgomery country hit, won the 1995 Grammy Award for Best Pop Performance By A Duo Or Group With Vocal and enjoyed an eleven-week run at #1 on the Billboard Hot 100 and a seven-week run at #2 in the UK. It was also nominated for Song Of The Year, as was the single "I Can Love You Like That," another remake of a Montgomery country song, the following year.

The group is comprised of Tony Borowiak, Jamie Jones, Delious Kennedy, and Alfred Nevarez, all from The Mojave, California, California City, California and Hesperia, California areas.

Many people often mistake All-4-One songs for being done by another popular 1990s R&B group, Boyz II Men, especially "I Swear" and "I Can Love You Like That". This is due to the very similar music style and height of popularity both being in 1994. Declining sales led to the group leaving the Atlantic Records label after the release of the album On and On in 1999, but even the shift in labels did not help shore up the group's flagging popularity, as the follow-up album, A41, and its lead single "Not Ready 4 Goodbye" both failed to chart in the US, although the follow-up, "Beautiful As You", was a minor Adult Contemporary hit. Their 2004 album Split Personality was given an Asia-only release.

All4One has recently signed a new record deal with Peak Concord. Their 7th album titled No Regrets will be released on August 25, 2009.