Mary Honeyball has been a Labour MEP for London since 2000, after 30 years in Labour politics. She is Labour's spkesperson for women's rights, culture and education. She previously served as a London Borough Councillor for eight years and a school governor for over 20 years. She was Chair of the Greater London Labour Party Women's Committee during the 1980s and spent three years as Treasurer of Emily's List, an organisation that helps Labour women campaign for seats in Parliament.

Before her election to the European Parliament, Mary had a distinguished career in the charitable and non-governmental sector. During the 1980s she ran the Council for Voluntary Service in the London Borough of Newham, before going on to work as a Senior Manager for SCOPE, the cerebral palsy charity.