Mordant holds the title of Officer of the Order of Australia and was Knighted in Italy for his contributions to the arts and business.
Having never left Europe, Mordant decided to take a gap year and travel through Afghanistan, Iran, and Pakistan.
[3] He started as an accountant at Peat Marwick, before becoming an investment banker at Ord Minnett on the Corporate Advisory side.
[4] Mordant remained at the group of companies, running the corporate advisory business for ABN in Australia until he left in 1999.
[9] A year later, he helped broker a $2.51 billion UAD deal between Malaysian-based Petronas and Australian energy company, Santos Limited.
[10] In 2010, it was announced that US-based investment bank Greenhill & Co. would be acquiring Caliburn in a deal worth $200 million USD.
In 2011, he was advisor to Coal & Allied after the media reported on a takeover offer by Rio Tinto, which valued the Australian-based mining group at $10.6 billion AUD.
The title was given by the Australian government "for service to the arts and to the cultural environment of Australia through philanthropic and executive roles, and to the community.
[15] During the same year, Mordant was the defense advisor to GrainCorp following its $2.68 billion UAD approach from Archer Daniels Midland.
[21] ERM at the time was the second-biggest energy retailer in the country, with Shell completing the acquisition for $617 million AUD.
He was introduced to Stewart Wallis and Leon Paroissien, who went onto become the founding director of the Museum of Contemporary Art Australia.
[30][31] It resulted in a fundraising effort to expand the Museum of Contemporary Art, with the Mordant family contributing $15 million towards the project.
[33] Since the start of the COVID-19 pandemic in 2020, Mordant spoke frequently about its impact on Australia's art scene and the struggle some galleries were facing.
[36][37] In December 2020, Mordant became an honorary professor at the Centre of Visual Arts (CoVA), part of the University of Melbourne.
It was suggested that Mordant would play a central role in CoVA's 10-year plan, which would see him forge closer ties with museums and educational institutions in Europe and the United States.
[38] Mordant is vice-chair of MoMA PS1 in New York,[39] board member of American Academy in Rome,[32] Executive Committee of the Tate International Council,[40] member of MoMA International Council,[39] Chair the Visual Arts Board for the NSW Government, chair the Lend Lease Public Art program at Barangaroo,[32] a member of the Advisory Board of Venetian Heritage in Italy, MCA's first International Ambassador for Museum of Contemporary Art Australia and Gallerie dell'Accademia in Venice.