The time for change is now. How do you create a movement of change?
For starters, educate yourself; find out what you need to know in order to change what needs to be changed.
I heard a story once from a woman who was questioning if there could be a gender pay gap in their company. In questioning a manager about this, his immediate response was that there was not a problem and there was no pay gap whatsoever, although no assessment had been done up until then. His assumption was based on his perception, not on fact. Her response was "do you think we are the one company who magically got this right, by accident?" when research showed the opposite. He had to concede it could be possible there was a gender pay gap.
Secondly, stop blaming the women. For example, we see from day one, women face more obstacles in the workplace. Catalyst research finds that women graduates get paid $4,600 less than men in their very first job out of business school and this gap only widens over time. According to the Center for American Progress, the wage gap stretches to $431,000 over woman's 40-year working career.
Read MoreWomen entrepreneurs don't need to go it alone
And contrary to a popular myth, it's not because women don't negotiate salary. Women do, almost as often as men: 47 percent of women vs. 52 percent of men negotiated for a higher salary during the hiring process.
The gap isn't caused by women having children and leaving the workforce; and it's not to do with women's lack of ambition. We know that women and men aspire equally to board service and executive positions, according to Catalyst research.
What we know is that this inequality starts from day one on the job and that not all leadership opportunities are created equal. Our research found that "hot jobs"—the highly visible projects and international experiences that predict advancement—are significantly given more to men than women (35 percent vs. 26 percent).
Even those women willing to relocate still miss out. Women are no more likely than men to turn down "hot" international assignments that can help their careers, but the problem is that they may not be asked. Because 70 percent of leadership development occurs on the job, this means women are losing out greatly.
To make change, companies need to be looking at how they recruit, retain and foster women's advancement. They must make intentional effort to sweep away any obstacles in their path, questioning whether men and women are treated differently because of their gender; set accountable targets aligned to business objectives; and finally disable the 'think-leader-think-male' default - just because the top of the house is all men, it doesn't mean leaders are all men.
Today, women are leaders in business, sports, and politics, and they are shattering stereotypes. But women can't do it alone. Men have many opportunities to level the playing field by role-modeling 'inclusive' behaviors to inspire other men to act too.
Studies show that inclusion benefits both women and men. Beyond gender, other dimensions of diversity are also found to be good for business: race, board member background, LGBT identity and nationality.
"Having diversity in your business is the key to success," said Gerald Schotman, Former EVP Innovation and R&D, Chief Technology Officer, Royal Dutch Shell, in March 2015. "Innovation and technology advances really are the result of diversity."
We see more and more business leaders stepping up to the plate and treating this as a business imperative. It is not about 'doing the right thing' but rather it is essential to the success of organizations.
Allyson Zimmermann is Executive Director of Catalyst, a nonprofit organization that promotes expanding opportunities for women in the workplace.