Women's Affairs Minister Hekia Parata is taking advice from business leaders across the Tasman, including New Zealand's Ralph Norris, on how to increase female leadership within Kiwi companies.

Parata's discussions with Norris were part of an Australian tour last week that looked at how our neighbour had boosted the number of women directors in its private-sector boards.

The Australian Stock Exchange has introduced a "report or explain" model that requires its members to set targets for improving the proportion of female directors and executives.

So far this year 31 per cent of new appointments to ASX 200 boards have been women, compared with just 5 per cent in 2009.

As CEO of the Commonwealth Bank of Australia, Norris had publicly set a target of having 35 per cent female managers by 2015, Parata said.

Norris believed change had to be led from the top and had invested in training for his executives about what the Australians call "unconscious bias".

The bank discovered that if a male and a female graduate with the same qualifications were hired to do the same job, within two years the man would be earning 4-5 per cent more than his female colleague.

"CBA have established a very senior management team that reviews recommendations for promotion to make sure unconscious bias is not skewing the way that salaries and performance bonuses are paid," Parata said.

She is stumped about why New Zealand companies have not adopted a more proactive approach to the issue. The NZX has not followed the ASX model or introduced any other initiatives.

If New Zealand wanted to lift its productivity it needed more diversity around the board table, she said. "How are we going to get the step change that we all agree we need in the economy?

"If you have a homogenous world view then you're going to continue to come up with the same kinds of ideas."

Increasing the proportion of women at the top was "explicitly" a priority for her ministry and resources would be allocated accordingly. She had been having animated discussions with Commerce Minister Simon Power about how to proceed, she said.

But she wouldn't be drawn on the possibility of quotas, which had been imposed overseas.

"I am keen for the NZX to see for themselves what's happening and take the opportunity for leadership."

A 2009 Goldman Sachs report found that closing the gap between male and female employment rates would boost Australia's gross domestic product by 11 per cent.

Parata had asked Goldman Sachs Australia's co-chief executive Stephen Fitzgerald to look at replicating the study in New Zealand.

ASX chairman David Gonski had also accepted an invitation to talk to business leaders about how the Australian model was working.

Parata would be talking to transtasman companies about when the translation would start happening here.

In Australia, there was an understanding that engaging in the process of closing the gap added value to companies' brands. The Sex Discrimination Commissioner at the Australian Human Rights Commission had established a Male Champions of Change group and invited 12 leading CEOs and chairmen such as Norris and Gonski to take part.

"It's been so successful that there's a waiting list of Australian businessmen who want to be included," Parata said.

* 9.3% - Proportion of women on NZSX 100 boards.

* 11.3% - Proportion of women on ASX 200 boards.

* 41% - Proportion of women on New Zealand public sector boards.