[1] He was head of many large organisations including chairman of the NRMA, Soul Patts, New Hope Group, Brickworks, Choiseul Investments, Queensland Mines Limited and NBN Television.
His father Thomas George Millner MC, VD[3][4] was a colonel in the Australian Army and his mother Mary was the daughter of businessman Lewy Pattinson.
At the breakout of World War II Millner enlisted in the Army Service Corps Officer Training School and was posted to Malaya.
[5] On his return, Millner completed a Materia Medica (Pharmacy) course in 1947 at the University of Sydney, and joined the family company, Soul Patts, where he rose to be director in 1957.
[7][8][9] Millner supported financially the Australian War Memorial, the Royal Botanic Garden, Sydney and served on the council of Newington College.