Most of the women who make up Norway's 'golden skirts' are non-execs

As an organisation is launched aimed at throwing open the doors of the boardroom to talented women without the use of quotas, it is worth looking at how a quota system imposed in Norway has worked – for companies and for women.

The 30% Club takes as its basis the idea that as more women join boards without the imposition of quotas, the more they can demonstrate the value they add. Founder Helena Morrissey, chief executive of London-based Newton Investment Management, believes: "By the time we get to 30%, the system will be self-perpetuating." In Norway, by contrast, , diversity in the boardroom is not only encouraged but required. In 2003, the state said at least 40% of the board members of listed companies should be women. Firms were given five years to comply. The figure is now 42% and a prominent group of Norwegian women, nicknamed the golden skirts, have turned themselves into multiple board directors.

Women Matter 2010, a report by management consultancy McKinsey, suggested that companies with gender-balanced executive boardrooms are 56% more profitable than all-male boards. So Norway, in theory, has not only struck a blow for sex equality, it has encouraged better management.

Or it might have done had the quota created more female managers. In fact, most golden skirts are non-executive directors. But Elin Hurvenes, head of the Professional Boards Forum in Oslo – which puts appointment committees in contact with talented women – suggests that this is about to change.

"Before the quota there were all these women who were banging their heads against a glass ceiling and suddenly they are being offered all of these non-executive roles," she says. "But now headhunters are starting to look to the boards and pick up women for executive jobs." The phenomenon is a powerful defence of Norway's quota against critics who highlight the discrepancy between women's 42% board representation and their single-digit share of executive positions.

Siri Hatlen, chief executive of the Oslo university hospital, and Eli Sætersmoen, chief executive of oil consultancy Falck Nutec, are the pin-ups of this career reversal. Both were portfolio directors of non-executive boards and were persuaded back to day-to-day management.

"The reason I was able to get the job was that, through the board experience I had, I developed a very good, solid network," says Sætersmoen. "If people have solved problems with you then companies feel safe because it is their friends who are recruiting you."

Not everyone is sure the non-executive route is the best way to a chief executive position. Mimi Berdal, the former chairman of Stabæk, Oslo's biggest football club, and someone who has gained from the legislation, is an unlikely critic. The former corporate lawyer still holds nine non-executive roles. "I am a grown-up woman and I have had a good varied career," she says. "But there are younger women who stopped their executive careers to become non-executives."

Berdal adds: "This is not an altogether positive development."