Thomas Graham Balfour (18 March 1813 – 17 January 1891) was a Scottish physician noted for his work with medical statistics, and a member of Florence Nightingale's inner circle.He was son of John Balfour, a merchant of Leith, and his wife Helen, daughter of Thomas Buchanan of Ardoch.He graduated MD at Edinburgh in 1834; FRS, 1859; Surgeon-General, Honorary Physician to Queen Victoria and compiler of the first four volumes of Statistics of the British Army.[1] He along with Dr John Sutherland were secretaries to the Sanitary Section of the International Statistical Congress in 1860, which was attended by Adolphe Quetelet, and to which Florence Nightingale submitted a paper.[4] He married in 1856 Georgina, daughter of George Prentice of Armagh, and had one son, Sir Graham Balfour.