Derek Mathias Tudor Williams FRIGS was born in Cardiff on 25 May 1929. He was educated at the Llandaff Cathedral School and afterwards at Radley. After considering a career as a barrister, he joined the practice of his father, Tudor Williams, a leading chartered surveyor practising from Cardiff and Pontypridd. Upon qualifying he remained with the family practice, eventually becoming senior partner. Williams remained a practising surveyor until his death, but gave increasing time to travel and golf and to pursuing his interests in opera, ballet, the theatre, photography and, especially, contemporary art. He died on 6 November, 1984.

Williams’ friends and associates remember him as a private yet kindly and gregarious man with a tendency towards perfectionism. He had no specialist knowledge of art, but derived immense satisfaction from building his collection, keeping it on display at his several addresses. Williams often expressed his concern that works donated to museums often remained in storage, hence the emphasis in his disposition as to display. His bequest and the long term loan of his collection have fulfilled his wish, enabling visitors to Amgueddfa Cymru – National Museum Wales to fully engage with modern and contemporary art of exceptional quality.