Women make up 50.8 percent of the population in the U.S. and earn more than 57 percent of undergraduate degrees and 59 percent of master's degrees. Yet they make up only a small percentage of CEOs at Fortune 500 and S&P 500 companies, according to research from the Harvard Business Review.

While it's clear women have the skills needed to be effective leaders, there's a lack of opportunity available. A 2018 report called Women in the Workplace found that only 38 percent of companies set targets for gender representation.

Seeing women in leadership positions is not only important for representation, but it also helps inspire other women. Eighty-six percent of U.S. women report that seeing other women in leadership positions breaks down the barrier to imagining themselves in those positions, according to a KPMG Women's Leadership Study.

One such leader paving the way for women is Sally Susman, Executive Vice President and Chief Corporate Affairs Officer at Pfizer. Susman, whose experience spans over three decades, previously held top roles at Estée Lauder and American Express. She also held appointed positions in the Clinton and Obama Administrations and serves as co-chair of the board of the International Rescue Committee and on the board of WPP plc, an advertising and marketing company based in the U.K.