Once upon a time, corporate America was a boys-only club, but the rules are slowly shifting even at the top of the ladder. More women than ever are running the most successful businesses in the U.S.: seven female CEOs made the Fortune 500 list in 2002 and 2003 compared to 18 women who made the list in 2012. To spotlight these business movers and shakers and continue our celebration of Women's History, here's a look at five female CEOs who are hammering away at the glass ceiling and making a major impact on the corporate world.
Marissa Mayer – Yahoo! CEO Marissa Mayer shocked the corporate world when it was announced that she was leaving her longtime job at Google to join the team at Yahoo! as their new president and CEO. Although Mayer considered the transition a "reasonably easy decision," according to Forbes, managing a company with falling stock prices and layoffs may not have been as much of an obvious choice to the public. Mayer's already taken Yahoo! in a new direction, making headlines when she recently required all employees to work in the office instead of telecommuting. Her tenacity as a CEO, even while she was an expecting mother, shows that women can do it all in the workplace.
Ginni Rometty – IBM CEO Virginia "Ginni" Rometty took control of IBM as president and CEO in January 2012, breaking a 100 year tradition of men leading the company. Rometty was rated No. 19 in the 2012 Fortune 500 list, outranking most of the men in corporate America. She was also ranked No. 1 in Forbes "50 Most Powerful Women in Business." One of the first initiatives that Rometty put into action as CEO is a five-year plan to promote revenue growth by using new markets in technology.
Indra K. Nooyi - PepsiCo CEO Through following her business mantra known as "Performance with Purpose," Indra K. Nooyi has carved out a leadership style that is all her own. Nooyi has used her power as chairman and CEO of PepsiCo to focus on providing healthier alternatives while growing the beverage company's global strategy. She's ranked 41 in the 2012 Fortune 500 listing, leading one of the largest food and beverage businesses in the world.
Rosalind Brewer – Sam's Club CEO Rosalind Brewer has broken barriers not only as a woman but as an African-American. Brewer took the helm of Sam's Club as president and CEO in February 2012, becoming the first woman and African-American to run a division of the powerhouse corporation Wal-Mart. Although she didn't appear as part of the Fortune 500 in 2012, she's been recognized by Fortune magazine as one of the "50 Most Powerful Women in Business" in 2010, 2011 and 2012.
Meg Whitman – Hewlett-Packard CEO When it comes to running multi-million dollar corporations, Meg Whitman has quite a bit of experience under her belt. Before becoming the CEO of Hewlett-Packard – ranked in the top 10 of the Fortune 500 companies of 2012 – Whitman was also the CEO of eBay for a decade, making her a recognized and respected force in the technology market. Her status as a prominent figure even stretched beyond the corporate realm, as she had a serious – albeit unsuccessful – run in politics as a top candidate in the 2010 gubernatorial race in California.