In 1957 he moved to his third Cambridge college when invited to become the master of Downing College, where he would remain for the rest of his life. As master he took a full part in the administrative, cultural and social life of the college, occasionally preaching in the college chapel and supporting the undergraduate music club and boat club. He oversaw a rewriting of the college statutes and introduced a maximum term for a master of fifteen years, by which he chose voluntarily to abide although it did not apply to him.