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Introducing the newest class of Fortune's 40 Under 40
Introducing the newest class of Fortune's 40 Under 40 · Fortune

We may think we live in the age of the tech unicorn.

But disruption is coming at us from all corners of industry, as our 2015 ranking of the most influential young people in business shows. There are tech names here, yes, but also stars in health care, autos, finance, food, real estate, comedy, and even ultimate fighting (welcome, Ronda Rousey). The one thing these mavericks have in common: They make their own rules.

For the first time, our list is 100% brand-new; as a result, we’ve named 17 select alumni of the list—some still under 40, many not—to our inaugural 40 Under 40 Hall of Fame.

What exactly is the 40 Under 40?

The 40 Under 40 is a measure of power and influence. Many moons ago—from 1999 until 2003—we ran a different version of the 40 Under 40 list: a ranking purely based on wealth. It was during the first dot-com boom, and the list was a way to showcase the striking fortunes accumulated by the era’s hotshots: Michael Dell, Jeff Bezos, Pierre Omidyar, Marc Andreessen (“Really Young, Really Rich,” read our cover in 2000). We retired that list soon after the bubble burst and much of that wealth vanished.

But in 2008, in the midst of the financial crisis, we started noticing that young people were doing some awfully significant things, whether in the financial world (Meredith Whitney had just made her bold call against Citigroup), in the tech world (Facebook was beginning to crank into high gear), or in other industries (Kevin Plank’s apparel upstart Under Armour was giving Nike a real run for its money). There seemed to be a movement afoot, and we decided to chronicle it with a list–one that, rather than being about money alone, was about achievements, ambition, and influence.

This is the seventh year of the list in its current form. (In 2013, we compiled a book, Zoom: Surprising Ways to Supercharge Your Career, that told the inside stories of some of the list’s most inspiring alums.)

Who creates the 40 Under 40?

Each year, the 40 Under 40 draws a large team of reporters, writers and editors. Each person picks an industry or area of focus, then they go hunting: talking to experts, digging up documents, interviewing key sources, and otherwise shaking the trees to come up with a long list of suggested candidates. From there, it’s a long, intense process whittling the ideas down to a mere 40 names. The last final decisions are always the hardest.

Which Fortune staffers and contributors compiled the list this year?

This year’s 40 Under 40 team includes: Daniel Roberts, Rupali Arora, Scott Cendrowski, Jonathan Chew, Jason Cipriani, Heather Clancy, Erika Fry, Stephen Gandel, Ben Geier, Erin Griffith, Claire Groden, Robert Hackett, Kia Kokalitcheva, Beth Kowitt, Adam Lashinsky, Michal Lev-Ram, Laura Lorenzetti, Chris Matthews, Tory Newmyer, Andrew Nusca, Luke O’Brien, Dan Primack, Leena Rao, Patricia Sellers, Benjamin Snyder, and Jen Wieczner.