As I join my colleagues to celebrate International Women's Day at this year's WIE Symposium in London, I laud the advancement of women over the past few decades, but know that we have much to do in order to achieve gender equality in our societies in the UK and the US.

Over the past four decades, society has broadly accepted and integrated women in the workplace. But, this has not yet reached the highest political offices, the boardrooms and the CEO offices of the corporate world. Women are still largely absent from leadership positions and are too often perceived to be incompatible with positions of power and leadership. This absence of women in positions of power is a painful reminder that gender equality is still an aspiration, not a reality.

When I was in law school in the US in the late 1970s, I could not imagine a female US President or Secretary of the Treasury, or even a CEO of a large company like Goldman Sachs or General Motors. Although I was fortunate enough to have a supportive family where my aspirations were treated no differently from those of my brothers, I subliminally believed that women were barred from making it to the very top. With no examples, my sights were limited.

Since then, great women like Hillary Clinton, Angela Merkel, Christine Lagarde, Margaret Thatcher, Meg Whitman; CEO of HP, Marjorie Scardino; CEO of Pearsons, Angela Ahrendts; CEO of Burberry and Virginia Rometty; CEO of IBM, have crashed through the glass ceiling. They lead the way for all other devoted and qualified women.

The younger generation of women is clearly getting the education required for the top ranks of career success. Over half of college graduates in the US are women, and more than 70% of valedictorians in the US education system are women. Women now account for over half the US labour force and are the majority in management, and professional occupations. In the UK, women account for over 56% of all college graduates and just under half of the workforce (46%).

Women are poised for the top jobs in business, government and civil society.

Despite all of this, women remain rare in top political positions in the US and the UK and in corporate board rooms and as chief executives. Sadly, neither the US nor the UK has a female head of state or head of government, and only 22% of members of parliament in the UK and 18% of members of Congress in the US are women. There are only five women CEOs in Britain's top 100 companies.

The ratio is even less in the US, where 18, or less than five percent, of the top 500 companies are led by women. Women represent less than 15% of board seats in the UK's top companies, and the US is not much better.

I do not believe that the reasons for the disparity between women and men in power are due to a lack of capability or temperament of women. Rather, the potential of women is being lost because of the failure of our society to understand and tap the potential of woman at the highest levels.

What can be done? Legislation alone will not solve this problem. Public declarations or quotas to increase the representation of women can only go so far - Lord Davies' Women on Boards report is case in point. The FTSE 100 are on track to the government's goal of having a minimum of 25% female board representation by 2017 - two years after his recommended deadline. The FTSE 250 fare even worse, and will miss the target by more than four years.

Rather, each and every one of us, individually and collectively, must alter the way we see the role of women in leadership positions. The business community - both men and women - needs to encourage and support more women in positions of leadership. We need to change the collective mindset of our society about what is appropriate for women, so more women feel that they will not just be a part of the work force but also part of the top leadership posts. Women leaders should be celebrated as the norm, not as aberrations.

If we can see it - if women who aspire for success can tangibly see the light at the top of the corporate or political ladder - then they can certainly be it. That is the key to winning the battle of gender inequality at the top of our society.

Today's WIE Symposium gets to the heart of this issue by celebrating successful women and reminding us that it is normal for women to want and expect to reach the top. The best way to celebrate today is to reaffirm for all women that the level of their success is based solely on their competence, hard work, and determination and never their gender. Most importantly, today is a day to inspire the next generation of women to pursue their dreams and flourish in their success.

Lynn Forester de Rothschild is CEO of EL Rothschild, LLC. You can follow her on Facebook, Twitter, and at Ldereport.com.

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