Joan Benham (17 May 1918 – 13 June 1981) was an English actress best known for her portrayal of Lady Prudence Fairfax in the ITV period drama series Upstairs, Downstairs. She was born in London and was the first cousin of Hollywood actress Olive Sturgess. Although her career mostly centred on television, Benham began her career appearing on the West End stage in the 1940s and continued to appear on the London stage periodically throughout her career. She appeared on Broadway as Helena in the 1954 revival of William Shakespeare's A Midsummer Night's Dream opposite Patrick Macnee as Demetrius.