Top positions of leadership in American businesses are still dominated by men, but top women CEOs in the US are breaking the so-called glass ceiling.

There are 12 Fortune 500 companies run by female CEOs.  These pioneers lead in diverse industries, come from diverse backgrounds, and pull down hefty pay checks. 

Some of them have been the movers and shakers who struck the biggest headline deals of the day.  Others managed corporate crises, turned around companies, and introduced bold initiatives.

Of the 12 women, the youngest is 49-years-old, the oldest is 62-years-old, and the most highly-compensated made $47.2 million in 2010.  Three of them are minorities.

Click Start to see Fortune's list.