Dr Soutphommasane has launched a report looking at the cultural composition of the Australian stock exchange, federal Parliament, the public service and universities.
That has led to calls for senior leaders in business and government to quit talking about inclusiveness and, instead, make it a reality.
Marlene Kanga was the first Asian-born board member of Engineers Australia.
"I had a very international outlook. Having been born overseas, having lived and worked overseas, I quite naturally took Engineers Australia and its work overseas."
The Indian-born engineer currently serves on the board of Innovation Science Australia and the Sydney Water Corporation.
She says, at times during her career, her cultural background has been a hindrance.
"There's always a little bit of a niggle as to whether you're able to do the job, simply because they haven't seen anyone else before you do the same kind of job. So you have to work extra hard to prove yourself."
A study released by the Race Discrimination Commissioner shows senior leaders in Australia remain overwhelmingly Anglo-Celtic or European in heritage.
It found, out of 201 chief executives at ASX 200 companies, only 10 were of non-Anglo-Celtic, non-European heritage.
None had an Indigenous background.
In federal parliament and the public service and among university chancellors, cultural diversity was also found to be dramatically under-represented.
The report's author, University of Sydney Business School dean Greg Whitwell, says bias and discrimination on selection committees remains a barrier to equal opportunity.
"The tendency is to have a bias towards choosing people whom you think are 'just like us,' who have a similar background, a similar attitude, just a similar sense of humour, a similar sense of looking at the world."
Professor Whitwell says the prevailing belief that leaders should be dominant and aggressive is another roadblock.
"In a sense, you can't win. If you're the stereotypical quiet, respectful Asian, then you're damned, because you're too quiet, you're too respectful. But if you're too aggressive, speaking loudly, you're forthright, then you're violating the stereotype, which, in turn, leads the selection committee to think negatively towards you."
Australia Post and Optus are among the few Top 200 companies in Australia to have appointed culturally diverse leaders.
DAWN, an organisation that advocates for diverse leadership, says there is a pool of diverse talent ready to utilise.
Chief executive officer Dai Le says organisations need to look into how to harness it.
"I think we need to look at quality. I think we need to look at capability. Because we just cannot have just one group of people on boards, because there's no diversity of thought, no diversity of perspective."
The study calls for senior leaders to make it their personal mission to advance cultural diversity and for organisations to set diversity targets and gather data to track their progress.
Race Discrimination Commissioner Tim Soutphommasane says Australia needs to be honest with itself and recognise it still has work to do to be truly inclusive.
"I think the business community is ready to take the next step and to ensure that cultural diversity isn't just about our food and festivals but about giving substance to our multiculturalism."
