Young was educated at the Parliament Hill School for Girls in London and went then to the New College of Speech and Drama, where she received a diploma in dramatic art in 1975, and a teaching certificate one year later. In 1988 she graduated from Middlesex Polytechnic with a Bachelor of Arts in Contemporary Cultural Studies.
Young worked as a professional actress from 1976 to 1984, and had been a residential social worker in the London Borough of Islington from 1971 to 1973. Her most prominent role as an actress was in children's sitcom Metal Mickey which ran from 1980 to 1983. In 1985, she became co-director and training and development manager at the Haringey Arts Council, a post she held until 1989.
From 1990 to 1992, Young was lecturer in media studies at the Polytechnic of West London. In the following she was lecturer, senior lecturer, principal lecturer, Professor of cultural studies and in the end Emeritus professor at the Middlesex University. In 1995 she published Fear of the Dark: Race, Gender and Sexuality in Cinema.
Young became Project director of the Archives and Museum of Black Heritage in 1997, she was Commissioner in the Royal Commission on Historical Manuscripts in the years 2000 and 2001, and Chair at Nitro Theatre Company in 2004.
Young was appointed an Officer of the Order of the British Empire (OBE) in the 2001 New Year Honours.
From 2001 to 2004 she was head of culture at the Greater London Authority, following which she was created a life peer on 22 June 2004 taking the title Baroness Young of Hornsey of Hornsey in the London Borough of Haringey.
Young's other public appointments have included English Heritage’s Blue Plaques Committee, membership of the board of the Royal National Theatre, the South Bank Centre, and the board of Governors of Middlesex University, chairing the Arts Council’s Cultural Diversity Panel, and membership of the board of Resource, the Council of Museums, Archives and Libraries, and a commissioner on the Royal Commission on Historical Manuscripts. She has also chaired the judging panel of the Orange Prize for Fiction.
She takes an active interest in ethical issues in international trade, particularly the garment industry, is a Trustee of the Aid by Trade Foundation and is an honorary associate of the National Secular Society.
In 2013, she was a signatory to a campaign for women to be able to inherit noble titles.
Lady Young of Hornsey has been married to Barrie Birch since 1984; they have one son.