Ever heard of the Howard and Heidi conundrum?
Facebook's chief operating officer Sheryl Sandberg often uses the term, which refers to the obstacles women still face at work.
In 2003, a professor at Columbia University gave matching CVs to two groups of students and asked them to judge who they preferred.
Both were judged equally competent, but they liked Howard, while Heidi was seen as ambitious to a fault and only out for herself.
The point has been highlighted in New Zealand by a recent government report, which revealed the pay gap between men and women has grown to its biggest point in six years.
The gap for median weekly earnings is now 11.8 percent, up almost 2 percent from a year ago.
A school librarian, who asked not to be identified, said gender bias was unmistakable at her work.
"I have been employed as a teacher in a school and I'm now employed as support staff at a school - I feel like I'm the same person with the same abilities and skills and qualifications and work ethic, but the way I'm treated is significantly different."
She said she felt her opinions weren't listened to and she was often ignored.
"Often I feel like I'm invisible," she said. "People make announcements and just forget to tell us to come... it's not that they didn't want to tell us but it didn't occur to them."
National Council of Women president Rae Duff said jobs predominantly done by women were undervalued.
"Sixty percent of women leave with a tertiary qualification, so we've got women who are more than capable, but they're just not getting into the higher management and pay positions."
One of the country's top executives believes getting more women on boards is part of the solution.
Joan Withers, director of Mighty River Power and TVNZ deputy chair, said women on boards would be looking at candidates for chief executive roles.
"If you're sitting at a board level you are absolutely going to be looking at the longlist for the CEO roles and the roles below that ... and saying 'where are the women on this list?'."
Salary inequality can be put down to a number of factors, and among them is women not negotiating hard enough for higher pay at senior levels, said Ms Withers.
"I just think you've got to keep going and say, 'hey this is not on ... this is what I think the market rate is for this role'.
"And maybe we don't push it far enough. If I reflect on my own career I probably didn't push it far enough."
In August, a survey by Cartoon Network found boys were paid an average of $460 a year in pocket money compared to $396 for girls.
Ms Duff said parents needed to take greater responsibility for their children's view of the world.
"We need to stop looking at it solely as a workplace issue, but society's issue," she said.
"We need to change our way in which we get young women into careers - we need to make them look wide and be free in their choice of career."
Quotas and parental leave
The World Economic Forum's most recent annual report found New Zealand women were among the most educated in the world but, for pay equality, the country ranked 33rd out of 142 countries.
A writer on inequality, Max Rashbrooke, said it was harder for women to climb the career ladder.
"There's still a very powerful bias against women, particularly towards those who stand up for their rights," he said.
"Men in positions of power who are dealing with men who are asking for a pay rise say 'good on them, they're being assertive'.
"Their reaction to women who are being assertive is 'this is someone who's causing trouble'."
Parental leave is often given as a simple excuse for the gap - women leave to look after their children and suffer the consequences if, and when they return to work.
Mr Rashbrooke said it was unfair.
"The problem is nothing to do with those individual women, but that companies aren't very forgiving of people who want to work part-time or flexibly."
He pointed to Norway as a good example of a country that had narrowed the pay gap - with the World Economic Forum ranking it the world's best on the gap, along with Singapore.
The Scandinavian country passed a law in 1993 requiring parental leave to be shared between parents. Before then, only 3 percent of fathers did so. In the last recorded year, 90 percent of fathers took leave.
But Law Society executive director Christine Grice said mandatory quotas were not necessarily the answer, and women needed to be appointed on merit.
She said law firms were improving, but not there yet.
"There are an equal number of men and women in the $100,000 - $150,000 pay bracket, but above that, only 15 percent were women."
'Glass basement' also important
Council of Trade Unions president Helen Kelly agreed attitudes needed to change if women were to be treated fairly, but said there was no silver bullet.
"We should look at the issues with hours of work and to provide security of employment, particularly in part-time work," she said.
"Collective bargaining should be provided - one of the big contributors to the pay gap is that men will often start at a higher rate, and that continues through their careers."
She said the emphasis should be on the "glass basement" roles.
"Women are working in very low paid and undervalued jobs and that's where the emphasis should be," she said.
"We're talking about the rest home workers, the retail workers, the clerical workers, the school support staff who are purely paid a low wage because they're female-dominated occupations."
Mr Rashbrooke said social progress had made a big difference over the past 30 years, but inequality was preventing the gap being bridged.
"There's been a huge increase in income gaps that are holding back the extra progress," he said.
"A lot of women work in industries with very little bargaining power, where pay rates have been low or declining for a long time.
"It's the opposite at the top."
The 2015 YWCA Equal Pay Awards will be held at an event this evening in Auckland. The awards, in their second year, focus on businesses that promote equal pay.