Sir Dawson Williams CBE FRCP (17 July 1854 – 27 February 1928) was a British physician and the longest serving editor of the British Medical Journal (BMJ). He gave up his medical practice to edit the BMJ and published influential studies into "mental healing" and bogus medications that exposed numerous preparations as "valueless" and containing only minute quantities of what was claimed. He retired in 1928 after thirty years of editorship.