Sir William Selby Church, 1st Baronet, KCB (4 December 1837 – 28 April 1928) was a British physician to St Bartholomew's Hospital, president of the Royal College of Physicians from 1899 to 1905 and president of the Royal Society of Medicine from 1907 to 1909 and also in 1893 (having briefly served after the death of Sir Andrew Clark, 1st Baronet earlier that year).

[3] He was educated at Harrow School, where he was captain of the cricket team and then went to Oxford University followed by a placement at St Bartholomew’s Hospital.

[2] He was elected president of the Royal Medical and Chirurgical Society in 1893 to replace Sir Andrew Clark, who had died in office.

[4] He chaired the executive committee of the Imperial Cancer Research Fund from its beginning in 1902 until July 1923.

[5] He was appointed a Knight Commander of the Order of the Bath (KCB) in the 1902 Coronation Honours list published on 26 June 1902,[6][7] and invested as such by King Edward VII at Buckingham Palace on 24 October 1902.