Martin Stanley Buckmaster, 3rd Viscount Buckmaster, OBE (11 April 1921 – 8 June 2007) was a British diplomat. He sat on the crossbenches in the House of Lords from 1974.Buckmaster was the elder son of Owen Buckmaster, 2nd Viscount Buckmaster, a barrister and Lloyd's underwriter, and his first wife, Joan Simpson.