As a Quaker and as a conscientious objector during the Second World War, she served in the Friends Ambulance Unit, first in Hackney, London, and then with displaced persons in Schleswig-Holstein and Bochum in Germany.
In 1964 she published Animal Machines, which describes intensive poultry and livestock farming. The book was said to have exposed the whole reality of intensive farming. It was published in seven countries and was the inspiration for the European Convention for the Protection of Animals Kept for Farming Purposes. In 1986 she was awarded an OBE.
- Oxford Dictionary of National Biography accessed 28/03/08
- Title Advances in animal welfare in New Zealand accessed 28/03/08
- Vegan Views (influences) accessed 28/03/08
- Animal Welfare Quarterly accessed 28/03/08
- Singer, Peter (2001). "Animal Liberation: A Personal View". Writings on an ethical life. London: Fourth Estate. p. 294. ISBN 1841155500.
- Animal Welfare Quarterly - A Tribute to Ruth Harrison
- Defra HTML document at the Wayback Machine (archived August 1, 2003)