The world's top firms will struggle to inspire the "millennial" generation with a reward culture based on endless hours in the office and networking built around heavy drinking and macho sports, according to business professor Elisabeth Kelan.

The senior lecturer at King's College London argues in her new book "Rising Stars" that 21st century graduates of both genders aren't willing to devote themselves entirely to any one firm in a world where changing jobs every two or three years is the norm.

"The millennial generation - both men and women - don't want to live their entire life to work," Kelan said.

"This is more pronounced for women because the long-hours work culture is not conducive to children. As a result, women often leave their jobs way before they actually want children."

Kelan's research shows that while women make up about 50 percent of entry level jobs, most organisations say only a third of their middle-management and 10 percent of top management are women.

This is partly because the women high-fliers in Kelan's book, who are lawyers, consultants, bankers, corporate executives, get disillusioned when men rise through the ranks faster than they do.

Some, fed up with long hours and little leisure time, decide to opt for something different - maybe consider starting their own businesses instead.

Others decide to go to business school to do an MBA to help give them a leg up the management ladder. But even here they find the environment is testosterone-driven.

Kelan gives the example of Iara, who works at an investment bank, but decides to do an MBA to help her career move ahead. She loves the MBA programme, but notices that women account for only about a quarter of her group.

She finds most of the activities on the course are designed for men and feels that in effect she is learning how to be "an honorary man."

Outside the classroom, it is no different. The dominant culture is "heavy drinking and extreme sports."

LIGHT BULB

Some companies are trying to break the mould.

Aviva (AV.L), the British insurance company, where women already make up 20 percent of its senior leaders, developed a reciprocal mentoring programme, in which a group of women and one gay man with leadership potential were mentored by the 11 members of the company's executive committee.

"This led to many 'light bulb' moments," Kelan said, where the executives realised their own privilege in having got to the top and why others might struggle to do the same.

The tone from the top, she says, is important in reshaping the organisation to allow diverse people to take leading roles.

The drive to get more women into corporate boardrooms could play a part in changing the "tone."

Norway, which introduced quotas for women directors in 2003, provides an interesting test case. Although it's not easy to assess how women affect the traditional male corporate culture inside the boardroom.

"It is quite complex," said Morten Huse, Professor at BI Norwegian Business School, who said a lot of existing research into this area was related to financial performance using quite basic models where it was not easy to see variations resulting from women's contributions.

"One core element we need to understand is how women make contributions inside the boardroom," said Huse, who is also a professor at the University of Witten/Herdecke in Germany.

Huse said research did show that if there were just one or two women they would tend to adapt to the existing boardroom culture while there was a big change if the number of women reached "critical mass."

"In Norway, we see that the traditional roles of independent directors are changing," said Huse.

His research identifies three types of independent directors at Norwegian companies - directors with some links to the company - known as insiders, directors with links to investors and true independents with no relationships to insiders.

He said that since the introduction of gender balance rules in Norway it was women who often replaced "true independents."

"So women have taken away much of the old boys' network."

Kelan has also looked at the Norwegian experience.

"I was sceptical of the women on boards initiative. We looked at Norway and did find that the more women are on boards the more likely the chairman is a woman or the CEO is a woman. So it does show that there is an increase in women taking leadership positions as a result of quotas."

Elisabeth Kelan's book "Rising Stars - Developing Millennial Women as Leaders" is published by Palgrave Macmillan. (Editing by Paul Casciato)

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