In 2010, Dame Alison Paterson - a Top 200 judge this year - was the first. Paterson was nominated by the judges as "an outstanding leader ... dedicated to best practice governance, forging partnerships with chief executives and other board members ... prepared to make tough decisions and big calls" when she considers it in shareholders' interests to do so.
It is also in the shareholders' interests to ensure more women are represented in senior management ranks.
But it's also about basic fairness.
And to ensure women do obtain the necessary skills and experience to even feature in the pipeline for chief executive appointments - let alone compete for and win the top jobs.
See video: Highlights from Deloitte Top 200 awards
It is extraordinary that women are still a rarity in the ranks of chief executives in New Zealand. There are many outstanding examples of female entrepreneurs like Wendy Pye, Diane Foreman and Erica Crawford driving private companies and accruing the personal wealth that goes with outstanding success.
Dame Suzie Moncrieff - founder of the World of Wearable Art and honoured as this year's Visionary Leader - has developed a business which is now a global phenomenon.
But when it comes to the leadership of listed companies the presence of women is woefully short.
In fact, no woman has yet been awarded Chief Executive of the Year.
But there are promising signs more women are being blooded at senior executive level. Westpac NZ - which was awarded Diversity Leader for 2015 - has equal numbers of women and men in its senior executive team.
Spark NZ's talented chief financial officer Jolie Hodson was also a finalist for the inaugural Chief Financial Officer of the Year award and has been marked by her chairman Mark Verbiest as one for the future.
See video: Red carpet with Holly Ryan
There is plenty of literature that diversity champions quote to illustrate that having both women and men at the board table is a powerful factor in driving results.
This is exemplified by Withers who chairs two substantial and well-performing enterprises Mighty River Power and Television New Zealand.
She has proved skilful in navigating the complex terrain which accompanies Crown chairmanships and led Mighty River Power through the successful completion of its IPO in 2013 against a background of strong political opposition.
She has since led the successful transition from a long-term chief executive with a strong industry background to a new chief executive with a new vision to capitalise on the company's renewable energy asset by championing the introduction of electric vehicle fleets.
At TVNZ she has led the board in a year that has seen the state broadcaster perform strongly against private sector and global digital competitors delivering a 15 per cent return on equity to the government shareholder.
Joan Withers also has a strong private sector record. She previously chaired Auckland International Airport where she championed diversity at board level with examples such as introducing a director with skills in social media and opening the door to younger talent through embracing an aspiring director programme.
Several of those aspirant directors can attest to Withers' nurturing style.
But its still taking too long for women to be strongly represented in the top ranks of New Zealand business.
Disclosure: Fran O'Sullivan was judging convenor of the Deloitte Top 200 Awards in which NZME is the media partner.
