Hook said the lack of women at the top was driven by a combination of issues.
"It starts with businesses not doing the right thing, not having the right policies, not having a diverse workforce and not having the right culture.
"There is a lot of work businesses and government organisations need to do."
"But it can't all be done by businesss. There are major societal issues."
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Hook said gender equality was not a "women's issue" but a family issue which would not be solved until there was a break-down in the perceptions around who should be the caregiver and who should be the bread-winner.
She said one change that could make a difference was giving paid parental leave to men and women equally as studies had shown giving men more involvement in their children's lives from an early stage resulted in more sharing of the responsibilities at home.
One of the changes she made as CEO of Deloitte in Australia was to give both women and men 18 weeks parental leave.
"When I got push back from leadership I said: 'this is not just about Deloitte, I am trying to change society'."
Hook pointed to Iceland and the Nordic countries which encouraged men and women to both take parental leave and where there had been a shift in the gender balance.
But she said change had to be led all at the top.
"A women only group is not going to get to get change especially not in a business world when men have all the power."
Hook was CEO in Australia for three and a half years before being selected to head the Asia Pacific region in September last year.
Her prior boss in Australia belonged to the Champions for Change a group of male CEOs trying to right the gender imbalance in business.
She was the first woman to succeed one of the original male champions. "In some ways I am a product of that."
Hook said sponsorship was more of a help than mentorship for those wanting to get to the top.
"I had lots of mentors people I would talk to who gave me good advice but the real difference was the sponsors."
Most of her sponsors were men.
She said a sponsor was someone in a position of power who had the ability to get you in a position where you have visibility and experience so when a role opens up people know who you are and think of you.
"I think women need sponsorship more than mentorship.
"Mentorship is good too but it is not going to get you to the top."
Hook said she had never felt disadvantaged being a women in getting to the top but had one thing she would have done differently in her career.
"I wish I had been a bit more bolder - taken more calculated risk. I got where I did by working hard and doing a great job."
She urged other women aiming for the top to have a broader view on what was possible at an earlier age.