Keisha was born in London, England from a Jamaican family, and started singing from an early age. She became friends with Mutya Buena in Kingsbury while at primary school. At the age of thirteen the pair met Siobhán Donaghy at a party, and formed a band together. In 1998, they were offered a record deal. Keisha was sixteen when the Sugababes had their first hit with Overload.

Keisha is now the only original member of the group due to the other two leaving; Siobhan in September 2001 (replaced by Heidi Range), and Mutya in December 2005 (replaced by Amelle Berrabah). Keisha is the only Sugababe to have a writing credit on a Sugababes song without any other members of the group, co-writing "Whatever Makes You Happy" on their third studio album, Three.

In late 2006, after the release of the single "Easy", Buchanan announced her plans to leave the Sugababes and launch a solo career. She added, however, that the group was only taking a short hiatus, and said she admired the move of Beyonce Knowles in leaving Destiny's Child and then returning to the group.

In the recent documentary entitled "Sugababes Uncovered" aired 19th December 2006, Keisha stated that she was not leaving the band and wished to carry on recording music under the Sugababes name. Keisha also revealed to the presenter, Dave Berry, that she had only met up with Mutya once since she announced that she was leaving the band and has found it difficult to continue a friendship with Mutya as she now does not see her.

--Wikipedia