Sir Robert Birley KCMG (14 July 1903 – 22 July 1982) was an English educationalist who was head master of Charterhouse School, then Eton College, and an anti-apartheid campaigner.
He acquired the nickname "Red Robert", as even his moderate liberal politics caused concern for the conservative members of the Eton school of governors.
His predecessor, Claude Aurelius Elliott was appointed provost and in his capacity as chair of the board of governors, living next door to Birley, he was able to keep an eye on Robert.