Facebook is great for women and men. We are enormously flexible. We care a lot about great opportunities for women, we push ourselves to make things as flexible as possible.

I realized that searching for a mentor has become the professional equivalent of waiting for Prince Charming. We all grew up on the fairy tale "Seeping Beauty," which instructs young women that if they just wait for their prince to arrive, they will be kissed and whisked away on a white horse to live happily ever after. Now young women are told that if they can just find the right mentor, they will be pushed up the ladder and whisked away to the corner office to live happily ever after. Once again, we are teaching women to be too dependent on others.

Women are not making it to the top. A hundred and ninety heads of state; nine are women. Of all the people in parliament in the world, thirteen per cent are women. In the corporate sector, women at the top - C-level jobs, board seats - tops out at fifteen, sixteen per cent.

Speak up. Believe in yourself. Take risks.

Being confident and believing in your own self-worth is necessary to achieving your potential.

Aggressive and hard-charging women violate unwritten rules about acceptable social conduct. Men are continually applauded for being ambitious and powerful and successful, but women who display these same traits often pay a social penalty. Female accomplishments come at a cost.

We hold ourselves back in ways both big and small, by lacking self-confidence, by not raising our hands, and by pulling back when we should be leaning in.