There are several things worth noting in the list, which remains as inspiring today as when it launched 20 (!!) years ago. “We thought about power as something much greater than simply profile, position, or pay,” Fortune editor Pattie Sellers wrote when she introduced the first ever list in 1998. “We measured power broadly—by revenues and profits controlled, influence inside the company, the importance of the business in the global economy, and its impact on American culture.”

And while that is still true, as Fortune chief Cliff Leaf observes, today women yield more power than ever before. “A telling data point? Just as in 1998, a woman— Margo Georgiadis—sits in the corner suite at Mattel,” he writes in his editor’s letter. “But in this year’s Fortune 500 issue, she was joined by a record 31 other female CEOs.” (Three of those names have since dropped, owing to company changes.)

And while racial diversity remains elusive, particularly in the C-Suite, it’s worth taking a moment to celebrate the arrival of Geisha Williams[hotlink ignore=true], the first Latina CEO in the <em>Fortune</em> 500, to the list. In March – almost 50 years to the day that she and her family arrived in the U.S. – the Cuban-born executive was tapped to run PG&E, California’s largest utility. Under her leadership, the $17.7 billion firm has already reached its 2020 goal of generating a third of its electricity from renewable sources.</p> <p>While Williams’ past reads as a classic immigrant success story, she is responsible for imagining an entirely different – and renewable – future, one with new pricing models and delivery systems that better serves the energy needs of customers and the planet. “The new model needs to reflect the new reality,” [hotlink]Williams told Fortune last June. She’s ready: “I’ve got revolutionary blood in my blood.”