He was educated at Rugby School and New College, Oxford. Where he was President of the Poetry Society and a friend of Dylan Thomas and attended lectures by Lord Clark.
Born in Holywood, County Down, was a Northern Irish solicitor, journalist, author and founding member, and first chairman, of the Ulster Architectural Heritage Society (UAHS). He was known to many simply as Charlie Brett. Between 1949 and 1950 he worked in France as a journalist with the Continental Daily Mail, where he is said to have mixed in anarchist and Trotskyite circles.
In 1956, the Earl of Antrim invited Charlie Brett to join the Northern Ireland Committee of the National Trust, on finding there were no books written to prepare himself for this to this Sir Charles resolved to write the necessary volumes.
In 1957 he became the first chairman of the Ulster Architectural Heritage Society, founded alongside, amongst others Lady Dunleath. Brett served as chairman for ten years and then as President from 1979 until his death.
With the National Trust he put his legal skill to use in order to establish a public footpath along the cliffs of the North Coast of Ulster. He also sat on the board of the Irish Architectural Archive in Dublin.
In 1971, he was appointed to the board of the newly created Northern Ireland Housing Executive.
He served as Chairman for five years from 1979, during which time 50,000 dwellings were built. He was asked to compile a list of historic buildings in Jersey in 1975. In 1986, Sir Charles became the first chairman of the International Fund for Ireland, established to encourage investment in Ireland.
Sir Charles was also involved in Northern Irish politics, being chairman of the Northern Ireland Labour Party for a time
In 1981 he received a Commander of the Order of the British Empire, this was followed by a Knighthood in 1990.