40 under 40

Welcome to Fortune’s 2017 40 Under 40, our annual ranking of the most influential young people in business. Read on to meet these disruptors, innovators, rebels and artists—and prepare to be inspired.

France's youngest leader since Napoleon swept the presidential elections in May, obliterating the two-party system that had governed the country for generations. The former Rothschild banker with globalist inclinations is already drawing fire, in part for a push to overhaul labor protections and cut payroll taxes (reforms business has long sought). Macron's honeymoon may be over, but after his fledgling party's big parliamentary win in June, his grand ambitions might just be in reach.

Emmanuel Macron

Zuckerberg has been a titan of industry for so long now, his youth is no longer remarkable or particularly noteworthy. He's a dad, philanthropist, tastemaker (seen his book recommendations?), and seasoned businessman, admired for his strategic vision and feared for his ruthlessly competitive streak. He's even rumored to be putting out feelers for a presidential run. We're guessing he'll be on this list for years to come.

Mark Zuckerberg

Didi Chuxing made headlines last year for buying Uber's China operations, besting its American rival in the battle for the biggest taxi market on the planet. Since then, the country's homegrown ride-hailing giant and its leaders -- Wei, CEO, and Liu, president -- have been on a tear: a $5.5 billion funding round valuing the company at more than $50 billion; investments extending its reach into Europe, the Middle East, and Africa; and a new A.I. lab in Mountain View, its self-driving competitors' backyard. Strap in: Didi's ride to dominance is just getting started.

Cheng Wei and Jean Liu

Possibly the only founding trio to remain in charge of a startup of this size nine years in, CEO Chesky, chief product officer Gebbia, and chief strategy officer Blecharczyk have steered Airbnb through its most eventful year yet. It launched a new platform for "experiences"; reached a detente with San Francisco; became profitable; launched a new brand in China; and saw its valuation climb to $31 billion.

Brian Chesky, Nathan Blecharczyk, Joe Gebbia

Ireland has long defined mass emigration. Yet remarkably, its new Prime Minister is the son of a Hindu immigrant from Mumbai. This former doctor is Ireland's youngest leader in centuries, not to mention its <a href="https://www.rte.ie/news/2017/0602/879755-fine-gael-leadership/">first-ever openly gay</a> one—no small detail in his devoutly Catholic country. Varadkar dismisses all that as irrelevant. Far more crucial is his ability to protect the Celtic Tiger against economic disaster when Britain exits the E.U. in 2019, and guarding Ireland's low-tax deals with tech giants. Many are rooting for his success. (For more on Varadkar read our feature <a href="http://fortune.com/2017/08/17/40-under-40-leo-varadkar-macron-trudeau/" target="_blank" rel="noopener">here</a>.)

Leo Varadkar

If you shopped online at all this year, there's a very good chance the Collison brothers helped complete your purchase. They're the cofounders of e-commerce behemoth Stripe, which is valued at $9.2 billion and handles tens of billions of transactions per year. The duo was born and raised in rural Ireland, and since founding the company in 2010, have become two of the youngest billionaires in the world. Now, even Amazon is on board, partnering with the company to process an undisclosed portion of its e-commerce transactions.

John and Patrick Collison

If you're a sports fan, or even if you're not, this has been the year of Serena Williams. In addition to setting the new record for number of Open-era grand slam titles (23) and being the highest-paid female athlete ($27 million over the past 12 months from June), the tennis pro has flexed her muscles on and off the clay court (and done it while pregnant to boot). In May, she joined the board of online survey giant SurveyMonkey, a month later she expanded her portfolio by investing in food startup Daily Harvest, and has spoken out forcefully for equal pay for women of color.

Serena Williams

The entrepreneurial duo has had a less eventful year than Travis Kalanick -- but that's a good thing. While Uber, their much larger competitor, struggles without a leader, Lyft has hit the gas. In July, the pair announced Lyft's new self-driving division, and launched a system that could one day enable car manufacturers to develop autonomous vehicles more quickly. They also raised $600 million in a funding round at a cool $7.5 billion valuation.

John Zimmer and Logan Green

Restaurant Brands (the massive parent to Burger King, Tim Hortons, and Popeyes) brought in about $4.1 billion in revenue last year with a market cap in the ballpark of $28 billion (including exchangeable units). The millennial at the helm? Schwartz, a partner at 3G who joined as CFO in 2010 when the private equity firm acquired a majority stake in the fast-food giant. Since taking the reins as CEO in 2013, he's worked to keep costs low, in part by urging employees to spend the company's money as if it was their own, a tenet he observes himself by always flying coach.

Daniel Schwartz

Armstrong is the CEO of Coinbase, which became the blockchain industry’s first “unicorn” after it raised $100 million in August, valuing the company at $1.6 billion. Armstrong, who now personally owns even more Ether than he does Bitcoin, is responsible for introducing much of America and beyond to cryptocurrency: The world’s largest exchange for trading digital currency, Coinbase’s customers have more than doubled in the past year, while trade volume in 2017 alone is roughly eight times last year’s total.

Brian Armstrong

<a href="http://fortune.com/ethereum-blockchain-vitalik-buterin/" target="_blank" rel="noopener">Vitalik Buterin</a> is the boy genius behind Ethereum, the world's second-most valuable cryptocurrency network behind Bitcoin. The twiggy, Russia-born software developer is arguably as successful an entrepreneur as Evan Spiegel or Brian Chesky. His visionary project has rocketed to a market cap of nearly $30 billion—as high as the private valuations Airbnb and Snapchat achieved—from $1 billion a year ago, when Fortune first placed him on its 40 under 40 list.

Vitalik Buterin

Anyone who regularly shops online likely uses the product Lütke has spent a third of his life building. Since he launched his e-commerce platform out of an Ottawa coffee shop in 2006, the low-key German-born programmer has fought to give Shopify's 500,000 merchants all of the attention. After the company's IPO the stock has increased by more than 100% to land at a nearly $10 billion market cap. Now, with year-over-year revenue up 75% in the second quarter, it might be Lütke's turn to step into the spotlight.

Tobias Lütke

Investors have been saying, WeLike to WeWork: This year Neumann and his coworking company raised an additional $2.5 billion in funding -- much of which is earmarked toward aggressive expansion in Asia -- at a valuation of $20 billion. Skeptics may balk at the figure, but WeWork now counts more than 160 locations and 130,000 members in 15 countries -- and is increasingly luring blue chips like IBM to its vision of hipster communal coworking nirvana. Next up: expanding WeLive and WeWork Wellness, the latter quietly piloted in 2016.

Adam Neumann

In 2014, Ek looked like a marked man. That was the year pop star Taylor Swift pulled her music from the streaming service over concerns about royalties, sparking furious discussion about the sustainability of its business model. Fast-forward to 2017: Swift is back on Spotify, which now counts more than 50 million paying customers, and the company is renegotiating royalty rates as it plows toward an IPO. Today a majority of music consumption in the U.S., some $4 billion in sales and growing, occurs via streaming. One big reason? Daniel Ek.

Daniel Ek

A soft-spoken Iowa native, Silbermann seems like an unlikely trendsetter. But he's built one of the Valley's hottest social media upstarts. Founded in 2010, Pinterest has become a vibrant repository for some of the most interesting trends on the Internet, from cars to weddings to architecture to tattoos. It's also a virtual gold mine of data for advertisers and retailers, propelling the still-private business to a valuation of roughly $12.3 billion in June. Its 175 million monthly active users have "pinned" more than 100 billion ideas to date, yet Silbermann says the company is still "only beginning to understand" how social media impacts consumers' lives. The most overrated trend of the moment? "Expensive juice."

Ben Silbermann

Tsai took the reins at Pou Chen, which churns out 300 million shoes per year for brands like Nike, Reebok, Adidas, and Puma, in 2012. The Taiwanese company, with revenues of more than $8 billion, was founded by the Wharton grad's father almost 50 years ago and now claims to be the world's largest manufacturer of athletic and casual footwear. Its operations are sprawling, with more than 400,000 employees in Mexico, Indonesia, China, and beyond. Even so, Tsai manages to keep an extremely low profile.

Pei-Chun Tsai

The youngest BlackRock executive reporting directly to CEO Larry Fink, Buckingham is tasked with long-term strategic thinking at the world's largest asset manager. Recently, she helped lead the firm -- and its $5.7 trillion under management -- to double down on algorithms making investment decisions over human stock pickers. Beyond tracking tech trends, the former emergency room surgeon also keeps a finger on the pulse of politics and regulatory changes.

Geraldine Buckingham

He's the world's hottest comic: He filled the massive Lincoln Financial Field in Philadelphia for his latest show, which he made into a movie that grossed $23.5 million. He's also starring in two major upcoming movies and planning another tour. But Hart is more than a funny guy. He’s opened a sprawling production studio, launched a streaming TV network, and has a tendency to invest in more brands than he endorses. How does he juggle it all? "I am addicted to success," Hart says. "And at the end of the day I want my name to have a powerful meaning. Every [business venture] I’m looking at as a building block. It’s helping me become the mogul that I want to be."

Kevin Hart

Cohen and Green travel quite a bit for work, but not to your typical conference destinations. The pair runs tech giant Alphabet's ambitious Jigsaw project, which aims to wipe out censorship, curb fake news, and aid free expression with online tools. "This is one of the most important challenges of our time," says Green, who recently flew to Iraq for pilot project "Redirect Method," which diverted people searching for terrorist recruitment information toward videos debunking propaganda instead.

Jared Cohen and Yasmin Green

Houston was 24 in 2007 when he cofounded Dropbox, a company that made it drop-dead easy for nontechies to store work files, photos, and more in the cloud. The company claims more than a half a billion users of its cloud storage and related collaboration tools and is continuing its push into business accounts. To be sure, Dropbox is facing off against much bigger competitors (hello, Google), but fans say its easy interface keeps it competitive. Now, investors, who valued the company at $10 billion in 2014, are salivating over the prospect of an IPO.

Drew Houston

Hu met Xia in 2012, when she was a journalist and he was working on connected cars for Ford in China. She requested an interview -- then stood him up, but they still kept in touch. Three years later, Hu persuaded Xia to pivot from cars to bikes. Along with Wang Xiaofeng (who's over 40) they started Mobike, now the world's largest bike-sharing company with more than 25 million daily rides in 160 cities worldwide, plus more than $1 billion in funding from the likes of Tencent, Sequoia, and Warburg Pincus.

Hu Weiwei and Xia Yiping

Snap is the company that Internet giants want to buy -- or crush. Headed by not-yet-30 Spiegel (pictured right) and his cofounder Murphy, the company behind the popular Snapchat photo app went public in March. It's been a bumpy road since: Snap's stock fell by about half, hitting a $15.4 billion market cap in August. And Facebook, which reportedly tried to buy it for $3 billion four years ago, is building a rival product. Now there's talk that Google (which apparently considered a $30 billion bid for the startup last year) is working on a similar product of its own.

Evan Spiegel and Bobby Murphy

It's been a busy year for Lake, founder of one of the Valley's hottest e-commerce upstarts, and it's about to get busier. Stitch Fix -- her online retail and styling company -- has dramatically expanded its product offerings in recent months, including adding clothing for men and plus-size women. In July, the company reportedly filed confidentially for an IPO. It's one of the most hotly anticipated public debuts coming down the pike (despite increasing competition from Amazon), with a valuation expected to land in the $3 billion to $4 billion range.

Katrina Lake

In his 14 years at one of the country's largest shopping center operators, Flynn has rocketed through the ranks, holding both the COO and CIO jobs before landing in the corner office last January. Kimco, with an $8.4 billion market cap, has weathered retail's storm by shedding weak properties (including $5 billion worth in the last five years alone) and redeveloping high-performing ones. The result is an occupancy rate of 95.5%. Still, Flynn is focused on the next big thing. "Retail always changes, and real estate will always change along with it," he says.

Conor Flynn

It was the blog post that touched off one of the most significant sea changes in the tech industry in years. Fowler's missive, "Reflecting on one very, very strange year at Uber," about the sexual harassment she experienced at the ride-sharing giant, sparked a conversation about Uber's culture that gave way to a shareholder revolt, prompting CEO Travis Kalanick to step down. Soon, other women across the Valley were going public with their own stories of unprofessional conduct (more resignations followed). These days, Fowler is editing Stripe's new quarterly publication, aimed at engineers.

Susan Fowler

The Harvard-educated Iraq vet is pushing House Democratic leaders -- whose average age is above 70 -- to make room for fresh faces. He's also leading a new national security task force, as well as a Future of Work Task Force, and serving on the House Armed Services and Budget committees. Cue rumors for a 2020 presidential run.

Seth Moulton

In 2014, Stefanik, a Republican from New York, became the youngest woman ever elected to Congress. The Harvard-educated moderate now serves on the House Armed Services Committee, where she's the chair for the subcommittee on Emerging Threats and Capabilities, and the Permanent Select Committee on Intelligence, among others.

Elise Stefanik

Dmitri Alperovitch outs spies for a living. His cybersecurity firm, CrowdStrike, raised its profile last year with its investigation of the massive data breach at the Democratic National Committee, attributing the attack to Russian agents and triggering fears over election interference. Alperovitch even got a nod from President Trump when the leader (erroneously) called out CrowdStrike as "owned by a very rich Ukrainian." (It's assumed he was talking about Alperovitch, who is a cofounder and was born in Moscow to Russian parents.)

Dmitri Alperovitch

By the time Nag had joined Apple, at age 23, she had dropped out of Stanford, founded a stem-cell research startup, and begun a medical investment accelerator. Now she oversees Apple's ambitious ResearchKit and CareKit programs that encourage developers to build health-related apps. If Apple succeeds, it could transform clinical trials from isolated events at hospitals to ongoing studies that capture vital signs from omnipresent sensors. Nag's personal goal is no less ambitious. "I want to put people in charge of their health," she says. "It's not about living with a specific disease or condition. It's about living. Full stop."

Divya Nag

In just under three years, Casper hit $200 million in annual revenue, selling stylishly designed “bed-in-a-box” mattresses, sheets, pillows and dog beds. Along the way, the company’s success has spawned more than 100 copycats and attracted a $1 billion buyout offer from Target. But Casper CEO Krim’s ambitions go far beyond shaking up the mattress industry. Krim wants Casper to become the “Nike of sleep.” Once it conquers sleep, they company aims to expand beyond the bedroom to become the kind of brand “that people are proud to showcase in their home,” Krim says. [This item has been updated.]

Philip Krim

The Chicago native has been subverting the music industry's traditional business model since he was a teenager, declining to sign with a major label and instead releasing his own streaming-only mixtapes, featuring unique strains of hip-hop splashed with sunny spirituality. Last year, he won the first-ever Grammys (three of them) for a streaming-only album and received $500,000 to debut the tracks exclusively on Apple Music. He's also a celeb endorser for Nestle, Nike, and even Twitter. Up next: He's set to star in the movie Slice as a pizza-delivery driver/werewolf.

Chance the Rapper

Sheffield is no stranger to volatility. He founded his Austin-based oil and gas company in 2008, and expanded it during the ensuing economic down years, leasing thousands of acres in the Midland Basin. It's been a wild ride since, with a successful IPO in 2014 that made Sheffield a billionaire, followed by years of sinking oil prices. Today, the price of a barrel is floundering around the $50 mark. But Parsley Energy is ramping up production. The quality that has most helped him succeed? "Optimism – the ability to view challenges as opportunities – has buoyed Parsley Energy during the inevitable tough times," he told Fortune. The quality that's sometimes detrimental? Also optimism, he says, i.e. "the stubborn belief that things will work out for the best."

Bryan Sheffield

Baldet is here to smash any preconceptions you might have had about the banking industry. She leads the team at J.P. Morgan that's developing Quorum, one of the most exciting corporate blockchain projects around. The open-source code is based on Ethereum (see entry <a href="http://fortune.com/40-under-40/vitalik-buterin-10/">No. 10</a>), and is designed to cater to big-business's needs -- like scale, performance, and privacy. A regular at hacker conferences, Baldet handily bridges the divide between Wall Street and the crypto set.

Amber Baldet

Garcia was working at an auto-financing company when he saw an opportunity in updating the car-buying experience that was "so big and so clear" he jumped. Three years after spinning out of DriveTime, Garcia, along with cofounders Huston and Keeton, have turned Carvana into a publicly traded company valued at more than $2 billion. This self-described "Amazon of cars" now has 1,375 employees and operates in 33 U.S. markets -- a fourfold increase in less than two years.

Ernie Garcia, Ryan Keeton, and Ben Huston

After creating a sensation a few years ago with Bevel, a line of shaving items for black men that reduces razor bumps, serial entrepreneur Walker is back with Form, a line of shampoos, conditioners, and other products aimed at a wide array of hair textures. Walker &amp; Co. Brands, seeking to fill a segment overlooked by major consumer-goods product makers -- people of color -- landed Sephora as Form's retail partner, enabling it to burnish its beauty credentials and move past the one-size-fits-all approach of the category. Says Walker: "Hair care just hasn't changed for 20 years."

Tristan Walker

Cloudflare tangles with some of the nastiest people on the web, defending its massive customer base from cyber-bad guys of all stripes. So it's no surprise that Zatlyn credits grit as her most critical personal quality: helping propel her from a small town in Saskatchewan, Canada, to Harvard Business School, and on to build one of the most important security firms in the Valley (rumored to be heading toward an IPO). Zatlyn also has an idealistic streak, particularly when it comes to the open Internet, which she calls "the greatest invention in the last 30 years."

Michelle Zatlyn

At just 32, Cohen has already made history. He dropped out of college to build Chewy, alongside cofounder Michael Day, and quietly built the Florida-based online pet retailer into one of the fastest-growing e-commerce websites in the world. At first ignored by VCs, Chewy drew the notice of the Valley once it started smashing growth targets. Besides the millions in funding, Chewy raked in nearly $900 million in revenue last year, and in April sold the company to PetSmart for $3.35 billion in the largest e-commerce acquisition of all time.

Ryan Cohen

Hartz has worn many hats at Eventbrite. Together with her now husband, Kevin, she cofounded the online ticketing startup in 2006. In those early days, she fielded customer support calls (often late at night). As the company grew, she played a role in its marketing and recruiting efforts, before becoming CEO last year. Since she became chief executive, the unicorn company -- which raised $200 million in funding and generated $8 billion in gross ticket sales __ has officially reached profitability.

Julia Hartz

Guardant's founders Eltoukhy and Talasaz want to remake cancer screening with their "liquid biopsy" technology, which can sniff out DNA fragments in the blood that indicate cancer-related biological markers. The method has drawn plenty of interest -- and capital -- despite initial skepticism. Guardant raised $360 million in May, and aims to sequence more than 1 million cancer patients' DNA within five years.

Helmy Eltoukhy and AmirAli Talasaz

This more than 10-year-old health-tech firm, helmed by CEO Shah -- a college dropout (pictured right) -- and president Agarwal, raised the kind of money that unicorns dream about earlier this year, bringing in over $500 million at a valuation of more than $5 billion. Outcome says it has already outfitted more than 40,000 doctor's offices with touch screens and tablets that can deliver meditation apps, relevant medical information, and (of course) advertising to patients.

Rishi Shah and Shradha Agarwal

The brains behind the beauty upstart Glossier, Weiss has built her company into a millennial obsession, offering an array of natural-looking products on a tech-savvy platform. Announcing the company's fresh $24 million Series B fundraising round, Weiss wrote, "Glossier is cult, it's not niche." In July, Weiss announced plans for international expansion, adding, "Those French lessons are really coming in handy."

Emily Weiss

Janah's Samasource is on track to pull in $15 million in revenue this year by setting up workers in Kenya, Uganda, India, and other underprivileged parts of the world as remote freelancers for the tech sector, an arrangement that boosts their average wages from less than $2.50 a day to more than $8. Janah, who also founded a skin-care line that employs women in Uganda, stresses the importance of work -- not charity -- in fighting global poverty. Her new book, Give Work, which outlines that philosophy, comes out this fall.