Kathleen "Katie" Brien, better known as Katy B, (born 8 May 1989) is an English singer-songwriter and a graduate of the BRIT School. She is a Dubstep, RnB, funky, house and UK Garage singer and has also performed under the name Baby Katy.

She was born in Peckham, South London. Other BRIT alumini who have found success include Amy Winehouse, Jessie J, Leona Lewis and Adele who was in the year above Katy. Having been offered major label deals in 2009, she released her first single with the label Rinse in 2010.

The same year, she completed a degree in Popular Music at Goldsmiths, University of London.DJ NG's song "Tell Me", which she featured on as Baby Katy, was released on a white label and later signed to Ministry of Sound.

Katy B has collaborated with Geeneus to cover the Kevin Saunderson produced "Good Life" and the track "As I". She also provides vocals on the track "Hold Me" for The Count & Sinden's debut album Mega Mega Mega and features on Magnetic Man's tracks "Perfect Stranger" and "Crossover".

Geeneus, with whom Katy B collaborated with, works for Rinse FM. Following the official recognition of the station in June 2010 (formerly a pirate radio station), Rinse presented Katy B's first single, "Katy On a Mission", which was produced by Benga and was released on 22 August 2010.

The single reached number 5 on the UK Singles Chart and number 1 on the UK Indie Chart.Katy B performed at the London Jazz Festival in 2009 with Ms. Dynamite and is collaborating with Ms. Dynamite on her upcoming album.

Ms. Dynamite also featured on Katy's second single, "Lights On" which was released in the UK on 19 December 2010, where it debuted at number 4 on the UK Singles Chart.Katy B released her third single, "Broken Record which was released in the UK on 25 March 2011 and reached number 8 on the UK Singles Chart.

On the 4 April 2011, Katy B released her debut studio album 'On a Mission'. The album debuted at number 2 in the UK.