Barker worked for Age Concern between 1983 and 2007. She was created a life peer as Baroness Barker, of Anagach in Highland, on 31 July 1999[3] and is a Liberal Democrat spokesperson on the Voluntary Sector and Social Enterprise.[4]
Barker revealed in a speech to the House of Lords that she was in a same-sex relationship during the passage of the Marriage (Same Sex Couples) Act 2013.[5] She since became a Patron of Opening Doors London,[6] a charity which provided support for older LGBT people, and an Ambassador for the Albert Kennedy Trust.
Barker is Co-Chair[7] of both the All-Party Parliamentary Group on HIV, AIDS and Sexual Health[8] and the All-Party Parliamentary Group on Sexual and Reproductive Health in the UK.[9] In the House of Lords she also serves as Deputy Speaker (since April 2024), as Deputy Chairman of Committees, and as Liberal Democrat Spokesperson on the Voluntary Sector.[10]