History has been made in New Zealand's Supreme Court with a majority of woman judges sitting on the bench at today's hearing.

Photo: Supplied / NZ Law Society

The Chief Justice, Dame Sian Elias, has been joined by Justice Susan Glazebrooke and Justice Ellen France, with Justices William Young and Mark O'Regan sitting alongside them.

The legislation governing the Supreme Court provides that sittings must be presided over by the Chief Justice and four or five other Judges.

The case that will be heard today is an appeal relating to alleged age discrimination affecting airline pilots.

The Law Society was applauding the milestone and Chris Moore, who heads the New Zealand Law Society's women's advisory group, said it was a fantastic achievement for the profession.

However, he said women's progress in the law field was still slower than they would like it to be.

He said 68 percent of the judiciary were men and it was important the law profession fixed its gender diversity issues, especially around women returning to the workforce after having children.

"Frankly if we don't do that we will have women leaving the profession and we simply can't afford to lose that talent, so we need to be more flexible in the way we practice and we need to look at a lot of the unconscious bias areas where so many of us fall into traps."

But he said this country was doing a lot better than the United Kingdom where just one of the 11 Supreme Court Judges was female.

He said many who become judges have been practising as barristers and depend heavily on briefings from independent lawyers and while there are plenty of talented women doing that, they needed to be on show to gain recognition.

"Unless their male counterparts engage them and brief them, then it is going to be very difficult for them to show their wares so I think in New Zealand, the more we have an equitable briefing approach, the greater exposure our senior women in the profession will get".

"With that will be the recognition and hopefully still greater representation in the ranks of the appeal Courts."

In Australia, three out of seven judges in its highest court are women, as are four of the nine judges on Canada's Supreme Court.

In the United States, three of the nine Supreme Court judges are women.