The Institute of Directors says action needs to be taken to improve the gender statistics on publicly-listed companies, where 77 per cent have less than 30 per cent women directors on their boards.
Chief executive Simon Arcus said the figures were a "stark illustration" of how bad the situation was.
Thirty-two per cent of the top 122 NZX-listed companies had no women on their boards, and just 5 per cent of the companies achieved 50 per cent women directors.
"When you stand back from that and say, 'We're living in a modern, equal society', the figures aren't good enough, it's just not in line," Arcus said.
Arcus said the benefits and importance of achieving a diverse board for the success of companies had been well documented and it was time for real action to be taken.
"We don't need any more people that simply want to talk about the issue."
Boards needed to establish clear targets that management needed to meet. Exit interviews to record any disatisfaction on lack of diversity, keeping track on whether big, visible roles and opportunities were being given to men and women and recording who were receiving bonuses were all examples Arcus gave.
"While change is happening, it's just too slow."
The IOD found 10 per cent of the 122 companies had between 30 per cent and 39 per cent women directors and 7 per cent had between 40 per cent and 49 per cent. The institute has created a guide that offers five practical steps to help boards ensure they are attracting and retaining diverse talent in governance.
"It's the first time anyone has brought together a framework for thinking about diversity," Arcus said.
Susan Paterson, board director for a number of companies, has been a mentor in IOD's Mentoring for Diversity programme.
Paterson said the change needed to happen in the boardroom with each new appointment.
For every new appointment to boards an independent, objective recruitment practice had to be taken to be sure that a change for diversity would happen, she said.
"Instead of using your own network of people you know or an old boys' network, ensure people are going a bit wider ... They'll find that within the skill-set [needed] there are actually a range of diverse applicants that have those competencies they're looking for."
The guide is being sent to the chair of every NZX-listed company.