Mollison was born in Wonthaggi, Victoria, and graduated from Secondary Teachers College (now part of the Faculty of Education of the University of Melbourne).
Nevertheless, the Gorton Government's failure to appoint a director of the NGA required that Mollison become involved in the development of the design for the building.
[3] The new prime minister, William McMahon, announced the appointment of Mollison as acting director of the NGA in October 1971,[4] and tenders for construction of a Gallery building were called in November 1972 to house paintings which had been collected and displayed around Parliament House, in Commonwealth offices, including diplomatic missions overseas, and State Galleries since 1910.
in 1977 Mollison persuaded Sunday Reed to donate Sidney Nolan's remarkable Ned Kelly series to the ANG.
The new prime minister, Malcolm Fraser, announced the appointment of Mollison as director in 1977,[10] and the new Gallery building was opened by Queen Elizabeth II in 1982.