Between 1965 and 1977 she held production posts within the British Broadcasting Corporation, working on current affairs and further education television programmes. She then became a journalist on the British Broadcasting Corporation"s prestigious Panorama programme, and Thames Television"s This Week and presented the British Broadcasting Corporation 2 series Social History of Medicine. She has a strong interest in health issues, notably as a campaigner on Human Immunodeficiency Virus and Acquired Immune Deficiency Syndrome. She was a founder director of the National Aids Trust in 1987 and is also a patron of Help the Aged.
Between 1994 and 1997, Baroness Jay was the Chairman of the charity Attend (then National Association of Hospital and Community Friends).
In 2003, she was elected Vice-President of Attend. She was appointed a life peer on 29 July 1992 with the title of Baroness Jay of Paddington, of Paddington in the City of Westminster, and acted as an opposition Whip in the House of Lords.
In association with the shop workers" union, she led opposition to the liberalisation of Sunday trading hours. From 1998 she was Leader of the House of Lords, playing a pivotal role in the major reform that led to the removal of most of its hereditary members.
On 11 November 1999 the government"s reform bill was given Royal Assent and more than 660 hereditary peers lost their right to sit and vote in the Lords.
She retired from active politics in 2001. Before her resignation, Jay gave an interview in which she said she attended a "pretty standard grammar school", which was actually Blackheath High School, an independent school. She drew ridicule when she said she could understand the needs of rural voters because she had a "little cottage" in the country, which turned out to be a £500,000 house in Ireland, and she also had a "substantial property" in the Chilterns.
After her party"s election victory in 1997, she became Health Spokesman and Minister for Women in the House of Lords. Among numerous non-executive roles that she has taken on since retiring from politics, she was a non-executive director of British Telecom Group. She is currently co-chair of the cross-party Iraq Commission (along with Tom King and Paddy Ashdown) which was established by the Foreign Policy Centre think-tank and Channel 4.