John Anthony Hardinge Giffard, 3rd Earl of Halsbury FRS^[1] (4 June 1908 – 14 January 2000), was a British crossbencher peer and scientist. Halsbury succeeded to the title in 1943.^[2]

Giffard was educated at Ludgrove School (where a schoolmaster inspired an interest in astronomy) and Eton. His years at Eton were highly successful, as he was a house captain, rowed in the school eight, and was elected to the small band of school prefects known as Pop.^[3]

Giffard was Managing Director of the National Research Development Corporation 1949–1959, after having been Director of Research of Decca Record Company 1947–1949, and previously worked for Lever Brothers, and Brown-Firth Research Laboratories. Subsequently he served on many public bodies, including chairing the Committee on Decimal Currency (1961–1963). Between 1966 and 1997 he was Chancellor of Brunel University.^[2]

He was President of the British Computer Society during 1969–70.^[4] In 1970 he was awarded an Honorary Fellowship of the British Psychological Society.^[5]

In addition, he was also a friend of J. R. R. Tolkien and was one of the few people to read The Silmarillion in Tolkien's lifetime, in 1957.^[6]

His grandmother was the Edwardian couturiere Lady Duff-Gordon, otherwise known by her professional name Lucile, who was a survivor of the RMS Titanic disaster.^{[citation needed]}