40 under 40

Welcome to Fortune’s 2015 40 Under 40, our annual ranking of the most influential young people in business—for the first time, 100 percent brand new. Read on to meet these disruptors, innovators, rebels (and, yes, unicorns)—and prepare to be inspired. <a href="http://fortune.com/2015/09/24/2015-40-under-40-intro/" target="_blank" rel="noopener noreferrer">Read more about the list here.</a>

Israeli-born Neumann is bringing startup culture to Big Business. With 54 locations across the U.S., Europe and Israel – twice as many as it had at the end of 2014 – <a href="https://www.wework.com/" target="_blank">WeWork</a>’s perk-filled, keg-friendly communal workspaces have attracted more than 30,000 members across the globe, including startups and, increasingly, <a href="http://fortune.com/fortune500/" target="_blank">Fortune 500</a> companies like American Express and Microsoft. A $400 million funding round this summer from Fidelity, J.P. Morgan and other major investors brought the company’s total funding to an estimated $1 billion and raised its <a href="http://fortune.com/unicorns/wework-11/" target="_blank">valuation to $10 billion</a>—double its $5 billion last December. Like some of its fast-rising peers in the so-called sharing economy, WeWork recently faced a labor dispute with an important part of its workforce—its cleaners, which it had employed as contractors. But the company responded by doing what its peers have been loathe to do: it hired an in-house janitorial staff as full-time employees, with benefits including equity.

Adam Neumann

Straubel says he’s “always been interested in electricity in general,” and that even in his youth he liked to tinker with wires and batteries (at age 14, he rebuilt an electric golf cart). Unlike most childhood passions, he turned his into a career. The Stanford Energy systems engineer and aeronautics whiz initially met with Tesla CEO Elon Musk to talk about electric planes— both are pilots—but ended up connecting over Musk’s dreams of an electric-car company. After helping persuade Musk to fund what would become Tesla, Straubel became CTO, and more than a decade later he’s still there, overseeing the technical and engineering design of the vehicles and often testing new hardware himself in his own Tesla models.

JB Straubel

San Francisco’s perennial number-two ride-sharing company has had quite the year of its own: In 2014 revenue and total rides grew fivefold, it hired a full suite of C-level executives, and earlier this spring it raised a $530 million funding round, followed by another $150 million, most of which came from Carl Icahn and now values the company at $2.5 billion. Green and Zimmer joined forces in 2007 when they founded Zimride, a ride-sharing service started on the campus of Zimmer’s Cornell University. <a href="http://fortune.com/unicorns/lyft-42/" target="_blank">Lyft</a> was started in 2012 as an on-demand extra but soon became their main focus; in 2013 they changed the name of the company and sold Zimride to Enterprise Holdings. This past year also saw the launch of Lyft Line, the company's carpooling service critical to achieving the founders’ goal of providing affordable transportation on a scale that will compete with public transit. And in early September, the company announced a major partnership with China’s Didi Kuaidi—which also invested in the spring funding round.

Logan Green and John Zimmer

There are basically two choices for ride-hailing apps in China – <a href="http://fortune.com/unicorns/didi-dache-6/" target="_blank">Didi Kuadi</a> and Uber – and the homegrown company remains the big dog, with 80% market share. Didi Kuaidi co-founder Cheng Wei is a cherubic-faced tech whiz who leaned on Jean Liu – the daughter of Lenovo founder Liu Chuanzhi and a former Goldman Sachs managing director – to finalize a merger earlier this year. The deal combined the Tencent-backed Didi Dache with Alibaba-backed Kuaidi Dache to create a giant capable of fending off rivals like Uber. In early September, the new company – which also has a new trans-pacific partnership with Lyft – was said to be raising $3 billion at a valuation of more than $16 billion, double its valuation in the spring.

Cheng Wei and Jean Liu

Graves was ride-sharing giant <a href="http://fortune.com/unicorns/uber-1/" target="_blank">Uber</a>’s first CEO, and was hired as the company’s first employee in 2010 after he responded to a recruiting tweet from cofounder and now-CEO Travis Kalanick in 2010 promising “BIG equity” in a yet-unknown startup (Graves’ response: “here’s a tip. email me. : )”). Graves—who was previously a management trainee at GE Healthcare and an unpaid intern at Foursquare—recruited the company’s first engineers and drivers; once the company took off in 2011, he became Kalanick’s number two, tasked with building teams and recruiting drivers in each city in the U.S. Now, with 2,300 employees reporting to him, Graves is focused on building teams in new growth areas like China and Southeast Asia. On the Uber board since its formation in 2010, his stake in the company is said to be worth close to $1 billion.

Ryan Graves

Pensions aren’t the sexiest part of a company’s business, but they can be among the most critical—and GM’s is one of the largest in the U.S. The 36-year old native of Chennai, India has been the chief investment officer of GM Asset Management since 2013—and became its CEO in early 2014—where she manages $80 billion in assets across the automaker’s retirement plans. Earlier this year she added VP of Finance and Treasurer to her resume, meaning she now has responsibility for capital planning, capital market activities, and worldwide banking, also participating in business development, risk management and investor relations. She joined the company in 2004 from UBS. The Harvard Business School grad—she moved to the U.S. to enroll—says that going to a legacy company rather than a startup like so many of her peers has been rewarding since she gets to “look at things from a fresh perspective.”

Dhivya Suryadevara

James Park is a man who knows how to stay calm under pressure, a trait he originally planned to parlay into a medical career. Instead, his tranquil demeanor has helped guide Fitbit to the forefront of the wearable industry, selling 4.5 million units and pulling in more than $400 million in revenue in its first quarter as a public company. Fitbit’s products are embroiled in competition with companies large (Apple) and small (Jawbone), but Park remains unperturbed. Markets are confident, too: Fitbit’s stock has climbed in the wake of its June IPO; its market cap is currently sitting just below $8 billion, making Park’s healthy stake worth nearly $700 million.

James Park

The country crooner turned pop mega-star was the single highest-earning musician last year, but that's not what earned her the respect and attention of the business world. It was her surprising and effective public stance against free music. First she stood up to Spotify, pulling her entire catalog and penning a Wall Street Journal op-ed that “music should not be free.” This year, she moved on to a bigger force: Apple. Just as the company was offering a trial period for its much-touted new Apple Music platform, Swift wrote a blog post pressuring it to rethink its artist pay model. (Apple had refused to pay artists during the service’s first three months.) It worked. Apple relented, making Swift the poster child for all artists hoping to reclaim their rights—and their revenue—in a digital world. Now that's major influence she can't shake off.

Taylor Swift

Narasimhan, a trained physician and former McKinsey consultant, has plotted his career to have the largest possible impact on public health. Now at Novartis, the giant Swiss pharmaceutical company (<a href="http://fortune.com/global500/novartis-167/" target="_blank">No. 167 on the Global 500</a>), he runs one of the industry’s largest drug development programs—overseeing 9,600 employees, 143 projects, 500 ongoing clinical trials and a multi-billion-dollar budget. Among the FDA approvals his shop has collected this year include one for a promising new heart-failure drug (Wall Street is also betting it’s a blockbuster). He’s also focused on using big data and technology to enhance medicine and human health.

Vas Narasimhan

Robins and two friends created <a href="http://fortune.com/unicorns/draftkings-81/" target="_blank">DraftKings</a> in 2012 to provide an alternative to season-long fantasy football. Three years later, the company has raised $375 million in funding and boasts a valuation close to $1.5 billion. The company is on a tear: It’s struck marketing mega-deals with Major League Baseball, Major League Soccer, NASCAR and UFC, as well as an exclusive partnership with ESPN. It’s bought up two smaller competitors (Draftstreet and StarStreet) as the daily fantasy industry explodes. Nowhere is the marketing assault more apparent than in the company’s hometown of Boston, where there is a massive “DraftKings Fantasy Sports Zone” at Gillette Stadium (New England Patriots owner Bob Kraft is an investor, too). DraftKings, suddenly, is everywhere—but so is FanDuel, its biggest competitor. The two are in an arms race for team partnerships and new users. Robins, a lifelong sports nerd, is unfazed, betting on his company’s technology and wider array of sports. This year, DraftKings will pay out more than $1 billion in total prize money. Is all of this gambling? Robins says no, and the law in most places calls it a “game of skill.” Five states disagree.

Read more about Jason Robins in "<a href="http://fortune.com/2015/09/24/draftkings-jason-robins-40-under-40/" target="_blank">This man is blowing up fantasy sports.</a>"

Jason Robins

Schwartz was a partner in the New York office of private equity firm 3G Capital when it took over a majority share of Burger King in 2010 and installed him as EVP and deputy CFO. He became CEO in mid-2013; a little over a year later, Burger King bought Canadian coffee-and-donut shop Tim Hortons to create Restaurant Brands International, and suddenly Schwartz was in charge of the world’s third largest fast-food company. From the company’s headquarters in Oakville, Ontario and Miami, the young CEO has brought the 3G mindset of extreme cost-cutting measures to both brands—a strategy that pushed Burger King’s pre-tax earnings up 11.5% last year and turned around once-flagging sales, bucking overall trends in fast food.

Daniel Schwartz

In an era marked by the rise of 140 characters, Oliver has bucked the trend by drawing viewers in huge numbers to his Sunday night HBO show Last Week Tonight. The Jon Stewart disciple tackles complicated and thorny issues with deep dives into injustices like tax exemptions for televangelists, the plight of chicken farmers at the hands of big processors, and even NSA surveillance through an in-person interview with Edward Snowden in Russia. Oliver claims to be no more than a comedian, but he has a powerful impact on the topics he touches, a phenomenon dubbed the John Oliver Effect. A Ninth Circuit court judge cited his segment on U.S. territory rights in a class-action suit in Guam. Oliver is single-handedly proving people can both laugh and be moved to action at the same time.

John Oliver

Whole Foods’ executive team makes decisions by consensus, so when Buechel was promoted into the top ranks in July his influence at the high-end supermarket chain skyrocketed. Not only is he the youngest in the group, but he’s also had the shortest tenure at the company—just two years versus 19 for the second most-recent hire. Since joining the company in 2013, the former Accenture consultant has forged a partnership with Instacart, implemented Apple Pay (making Whole Foods one of the first retailers on the payment platform), and is now testing the company’s first rewards program. But Buechel’s rise up the Whole Foods’ food chain is also a nod to the importance of technology in the company’s future. He’s working on systems that give full traceability into the supply chain and better inform customers about products’ nutritional and allergen information. He’s also heavily involved in shaping the company’s newly announced lower-cost 365 chain. Few details about the brand have been announced—except that technology will play a key role.

Jason Buechel

Robby Mook traces his history with Hillary Clinton back to the dark days of the 2008 Democratic primary, when the once-prohibitive favorite endured a slow-motion collapse across the map. His obsessive focus on organizing—both his own staff, down to 30-minute intervals, and the leave-no-voter-behind field program they assembled—produced a rare bright spot, helping her pull out an upset victory in the Nevada caucuses. The Columbia classics major’s no-drama style at the helm of that contest also yielded the “Mook Mafia,” a fiercely loyal corps of young operatives that now surround him as he captains Clinton’s second presidential bid. These days, his low-key resolve faces an even stiffer challenge as blowback from Clinton’s email controversy has once again knocked the frontrunner on her heels, raising questions about her campaign’s handling of the issue. How he adjusts for the recent events may be his greatest challenge yet.

Robby Mook

As a 20-something-year-old banker with the San Francisco firm Hambrecht &amp; Quist, Wintroub never went anywhere without his self-styled laminated map of the burgeoning Internet industry. He wasn’t just out to make a buck; he had an infectious desire, an almost evangelical need, to convince everyone this tech thing was going to be big. It was. And now so is Wintroub, the youngest-ever vice chairman of JP Morgan Chase, which bought H&amp;Q. Today Wintroub, a close protégé of the late, revered J.P. Morgan banker Jimmy Lee, heads the firm’s “Internet and digital media” practice. Still based in San Francisco, he’s advised Internet titans like Facebook, Alibaba, and LinkedIn. And he’s still preaching about the possibilities of the Internet, having been around since before these now-established behemoths existed.

Noah Wintroub

Years after initially getting turned down for a job at Google, Brazil-born Barra found himself in a plum perch leading the search giant’s mobile aspirations as vice president of Android. It came as a surprise when in late 2013 Barra announced he was leaving Google for the then relatively unknown Chinese startup Xiaomi—tech’s <a href="http://fortune.com/unicorns/xiaomi-2/" target="_blank">no. 2 unicorn</a>, valued at $46 billion. As vice president, Barra is tasked with leading the company into uncharted territory by ushering its inexpensive products to new international markets—growth areas that are more critical than ever for Xiaomi as China’s smartphone penetration reaches all time highs.

Hugo Barra

As an expectant mom, actress Alba saw a void in the market for less toxic, more sustainable household goods. The Honest Company is fast filling it, last year selling some $170 million worth of products like diapers and cleaning supplies in outlets like Costco, Target, Whole Foods and Nordstrom—nearly a threefold increase over 2013. Alba is also pushing into new geographies—South Korea is next and China is in the works—as well as categories, with Honest Beauty, a cosmetics and skin-care line launched earlier this month. <a href="http://fortune.com/unicorns/honest-co-64/" target="_blank">Part of the Unicorn Club</a> with a $1.7 billion valuation, The Honest Company could have an IPO on the horizon.

Jessica Alba

When brothers John and Patrick Collison founded and sold their auction and marketplace management system Auctomatic for $5 million in 2007, John was 17; his older brother 19. In 2009 they founded online payment processor <a href="http://fortune.com/unicorns/stripe-20/" target="_blank">Stripe</a>, John dropped out of Harvard, and the brothers moved to Silicon Valley (yes, the comparisons to Mark Zuckerberg’s path to founding Facebook have been made). Now Stripe, which allows companies to process payments in 100 global currencies – including Bitcoin – with just a few lines of code, has a $5 billion valuation; it counts Elon Musk, Peter Thiel and Visa and American Express as investors; and fellow 40 Under 40 companies Kickstarter, Lyft, and Instacart as customers. Next up for Stripe: ramping up hiring. The company expects to add another 200 employees in the next three months, bringing its head count to 500.
For more on Stripe, read "<a href="http://fortune.com/2015/07/28/stripe-payments-startup/" target="_blank">A billion-dollar startup earns its stripes</a>."

Patrick Collison and John Collison

At 17, Karen Fang hit a crossroads. Fluent in English (she won third place in a national speech competition), the China-born investment banker wanted to study overseas, but her parents would only let her go as far as Japan, where all she could say was hello and goodbye. That didn’t stop her. Fang completed a two-year Japanese language course in two months, and was enrolled in the highly ranked University of Tokyo by the next semester. She’s been on the fast road ever since. Five years ago, she was poached from Goldman Sachs—where she made her name convincing a number of large pension funds to hedge in the run up to the financial crisis—by Bank of America to run a first of its kind on Wall Street cross-asset, cross-industry structured-strategies group (“It’s about solutions, not products,” she says). She has since grown her group to 55 from 10, and Risk magazine named B of A the top structured product house on Wall Street in 2015. Last year, Fang was also tapped by senior management to streamline the bank’s deal approval process. In April, she was named a Young Global Leader by the World Economic Forum.

Karen Fang

Accenture’s youngest-ever global leadership council member runs its fastest-growing business. Under Swaminathan’s tireless direction, the $6 billion unit Accenture Digital is expanding revenue 30% year-over-year and winning recognition for digital marketing, business analytics, and mobility projects with clients like hospitality giant Marriott International and Swiss bank UBS. That’s not enough for the India-born executive, who has spent almost half his life working for the firm. Swaminathan engineered six acquisitions during the past 12 months, collectively investing $500 million in digital talent and technology. He manages 30,000 people. On the side, Swaminathan has advised more than 45 startups, including payments darling Stripe and small-business services pioneer Gusto. Companies in his personal portfolio were valued at more than $4 billion, as of early September. In his spare time, he logs 400,000 veritcal feet annually during two-week heli-ski trips.

Anand Swaminathan

Falzone’s company has developed a simple yet sticky technology: a point-of-sale system based on Apple’s iOS mobile platform. Under her direction, Revel has already sold 10,000 such systems to customers like Smoothie King and Tully’s Coffee. Over the last 12 months, the company doubled its employee count from 200 to 400; earlier this summer, Falzone closed on a $110 million investment round. She’s also inked partnerships with the likes of Intuit, a provider of software tools for small businesses, and recently signed a major enterprise sales deal with Apple. Next up? International expansion and, she says, an IPO in the next two to three years.

Lisa Falzone

Set aside, for a moment, the fact that business software company <a href="http://fortune.com/unicorns/zenefits-21/" target="_blank">Zenefits</a>—it offers cloud-based HR software that helps companies manage healthcare coverage—has reached 1,600 employees, 10,000 customers, and a $4.5 billion valuation in just two years. How its CEO and founder, Parker Conrad, got here is just as impressive: Conrad graduated from Harvard after flunking out, beat testicular cancer at 24, and was pushed out of his previous startup, SigFig, by his own co-founder. But even with $583 million in funding, a nosebleed valuation, and growth that shows no sign of slowing, Conrad says Zenefits feels like an underdog. The company competes with insurance brokers and business software incumbents alike, so “it feels like we’re threatened on every side,” Conrad says. Already he’s fought state regulators and an ongoing lawsuit with ADP. But he’s not deterred. “It’s so clear to me that we’re right.”

Parker Conrad

Stamos isn’t known for his restraint: Earlier this year, he publicly challenged Michael S. Rogers, the head of the United States National Security Agency and Cyber Command, at a security conference, for suggesting tech companies provide access to users’ encrypted data. At the time Stamos was Yahoo’s information security chief, and had been leading an email encryption project in partnership with Google—so the dust-up was personal. In June, Stamos jumped ship for Facebook where he now serves as security chief. (Uber had poached his predecessor in the role.) Among other projects, he’s now working out the kinks in the social network’s plan to drone-deliver the Internet to all regions of the globe—securely.

Alex Stamos

Ackerly was <a href="http://fortune.com/2015/09/24/will-ackerly-virtru-ex-nsa-anti-hacker/" target="_blank">once a whiz kid in the National Security Agency</a> (for a time using his technical skills in Iraq to help the American military track terrorists). Like Edward Snowden, he was disturbed by the extent of the NSA’s spying on regular citizens. Unlike Snowden, Ackerly didn’t leak the agency’s secrets. Instead, the lifelong tinkerer—as a child, he rewired a switch in the family basement to disable a light on his parents’ phone system so he could conceal his excessive modem use—invented a technology that can protect your email and data from anyone bent on stealing it, whether a criminal hacker or a government snoop. Ackerly’s company, <a href="https://www.virtru.com/" target="_blank">Virtru</a>, launched a web plug-in based on what he dubbed the TDF in 2014 and now has thousands of clients. Many are in the healthcare realm, and state and federal government entities have even begun using the technology, newly aware of their own vulnerabilities. Virtru also offers a free version that individuals can download and use on, say, their Gmail.
For more on Ackerly, read our cover story: "<a href="http://fortune.com/2015/09/24/will-ackerly-virtru-ex-nsa-anti-hacker/" target="_blank">Could this ex-NSA hotshot protect your email from hacking?</a>”

Will Ackerly

Orion Hindawi pitched the idea for an IT management company to his father, David, in 2007. Eight years later, the pair helms white-hot cybersecurity startup <a href="http://fortune.com/unicorns/tanium-62/" target="_blank">Tanium</a>. Valued at $3.5 billion, the company has raised more than $260 million in venture capital to date—more than half of that coming from Silicon Valley’s Andreessen Horowitz, making it the VC firm’s single largest investment to date. (The father-son duo’s last company, BigFix, sold to IBM for a reported $400 million in 2010.) Hindawi, a technical ace whose product scans and queries the machines on a corporate network in a matter of seconds, has little patience for what he deems to be distractions, he says. “Instead of figuring out which building in Shanghai a hacker came from, figure out how that hacker got data out of your insecure computers,” he counsels businesses, dismissing the specialties of rival cybersecurity firms. “Our industry at the end of the day needs to be more honest with our customers.”

Orion Hindawi

Frank Wang founded <a href="http://fortune.com/unicorns/dji-15/" target="_blank">Da-Jiang Innovations (DJI)</a> in his dorm room in Honk Kong just nine years ago. Now it's the world’s largest consumer drone business, with an estimated 70% of global market share. Skyrocketing demand for DJI's Phantom drone—an engineering marvel targeted to at-home enthusiasts, ready to fly right out of the box with an integrated camera—earned it a spot in the Apple Store in September. The FAA, which only this January opened up the U.S. skies for commercial operators, has so far approved ten times more DJI drones than its competitors. In May, Wang raised $75 million from Accel Partners at a lofty valuation of $8 billion. Even as regulators double down on safety and security concerns (yes, it was a DJI drone that crash-landed on the White House lawn earlier this year), Wang expects to pilot DJI to $1 billion in sales this year.

Frank Wang

During a pitch meeting for Mehta’s <a href="http://fortune.com/unicorns/instacart-51/" target="_blank">Instacart</a>, a venture capitalist left the room and returned with a floppy disk that contained the blueprint for food delivery business Webvan, a $4 billion, dot-com bust that sounded like Instacart. “Go home and study it,” the investor said (Mehta says he would have, if he knew how to open a floppy disk). What Mehta did know was that grocery shopping was ripe for a change. Instacart uses a mobile app that connects users with 4,000 personal shoppers who handpick and deliver your order in hours. It now operates in 18 metropolitan areas, partners with Whole Foods and Costco, and holds a $2 billion valuation. That fast expansion and big-name partnerships helped assuage those early investor worries; now, Mehta just needs to fend off Amazon, Walmart, Google and Uber, all of which want into the market.

Apoorva Mehta

In May, Cohen was named global head of M&amp;A for financial sponsors at Goldman Sachs, which usually leads all of Wall Street in the category (essentially, M&amp;A done by private equity firms). The high-profile role was arguably created with her in mind: Cohen started with Goldman as an analyst in 1999 and quickly rose through the ranks to partner and co-head of industrials M&amp;A -- an area where financial sponsors like private equity firms are a constant presence. Now she leads a new team that is bridging Goldman’s industry-specific M&amp;A functions with its financial sponsors groups, helping both and increasing efficiencies for clients. “It’s kind of a startup within Goldman,” she says. “We’re still working on the same sorts of deal, but now doing it in a different, better way.”

Stephanie Cohen

Jared Kushner, son of Charles Kushner and son-in-law of Donald Trump, has an unparalleled pedigree in American real estate. The 34-year-old, who took over as CEO of Kushner Companies at in 2008, could have rested on his laurels, presiding over the New Jersey real estate empire his father built. But much like Trump, Kushner instead used the corporate foundation his father built to lay siege on the grandest prize in American real estate: Manhattan. In 2014, his firm completed more than $2 billion in transactions, inking an ownership interest in 560,000 square feet at 80-90 Maiden Lane in Manhattan’s financial district, while buying up 2,000 multifamily apartments in New York, New Jersey and Maryland. That’s on top of the more than 12,000 residential units Kushner snapped up between 2010 and 2013, moves that look all the wiser as Big Apple property valuations remain hotter than Kushner’s beloved New York Mets.

Jared Kushner

The former VP of business development at high-end gym chain Equinox took over as CEO of SoulCycle, the sizzling hot cult cycling chain, in June. (Equinox owns 97% of the company.) One month later, SoulCycle filed for an initial public offering, tasking Whelan—an avid cycler herself—with seeing the company through its impending IPO and navigating her ambitious expansion plan. The chain, which started nearly ten years ago as a single indoor cycling studio in Manhattan’s Upper West Side, now has 38 locations across the U.S. And its IPO filing revealed something rarer than a unicorn: The business is already profitable, bringing in $112 million in sales and $26.5 million in net income last year.

Melanie Whelan

In era of app fatigue, the breakout success of <a href="https://www.periscope.tv/" target="_blank">Periscope</a>, a livestreaming video app launched in March, is rare. Within a week, the app captured a million registered users; in four months, it hit 10 million. Beykpour, who previously led mobile for ed-tech firm Blackboard, says Periscope is popular because it teleports viewers into the raw, unfiltered action, be it the immediate aftermath of the April earthquake in Nepal, a backstage view of a Taylor Swift concert, or musings of a bored teenager. It didn’t hurt public intrigue that Twitter acquired Periscope for a rumored $100 million before it even launched. Beykpour, who manages his team of 24 in a separate San Francisco office away from Twitter’s headquarters, says Periscope’s mission hasn’t changed since the deal: “In its most successful carnation, [Periscope] builds empathy and truth.”

Kayvon Beykpour

The El Paso, Tex. native already had the resume of a biotech wunderkind: she graduated from the University of Oxford with an MD and PhD, went on to serve as vice president of Cambridge-based Sirtris Pharmaceuticals – where she engineered the sale of the company to GlaxoSmithKline for $720 million – and eventually headed up GSK’s specialized R&amp;D unit, the Centre of Excellence for External Drug Discovery (CEEDD). In 2011, after seeing multiple friends struggle with fertility issues, she co-founded <a href="http://www.ovascience.com/" target="_blank">OvaScience</a> to bring to market a breakthrough innovation that uses a woman’s own mitochondria to “revitalize” older eggs before they’re fertilized, improving embryo quality for in-vitro fertilization. So far, ten babies have been born using the technology, and the company is on track to start commercializing the product next year—except in the U.S., where the FDA has yet to approve it. For now, Dipp has shifted her focus to slowing biological clocks overseas, where large markets in Japan and the Middle East are promising.

Michelle Dipp

In August, this No. 2 to <a href="https://www.taskrabbit.com/" target="_blank">TaskRabbit</a> founder-CEO Leah Busque snagged another big gig: a board seat at HP Inc., the printer-and-PC business that will be a publicly traded company after Hewlett-Packard’s impending split. Born in Detroit and raised by a single mother, Brown-Philpot went to college at Wharton, got her MBA at Stanford, and once worked as an M&amp;A analyst at Goldman Sachs. She joined Google in 2003. During her nine years in at the tech giant, she worked for Sheryl Sandberg (“a mentor”), headed online sales and operations for Google India, and founded the Black Googler Network, a key component of Google’s efforts around diversity.

Stacy Brown-Philpot

Sam Altman says the most important piece of advice he’s ever received came from Paul Graham, who last year hand-picked Altman to take over as head of his <a href="https://www.ycombinator.com/" target="_blank">Y Combinator</a>, the acclaimed startup incubator whose graduates include Airbnb and Dropbox: “Make something people want.” But the 30 year-old Altman – an alum of YC’s first founder class, where he launched his location-based social network app Loopt – has added an unofficial addendum, about making something people want more accessible. In his short time at the helm, Altman has increased the number and type of companies accepted into YC (222 graduates this year), held ‘Startup School’ seminars outside of Silicon Valley (most notably in London, plus an online version in partnership with Stanford) and reached out to women and minority entrepreneurs. “My goal is to double our impact every year.”

Sam Altman

You may not have heard of <a href="http://fortune.com/unicorns/github-50/" target="_blank">GitHub</a>, but you’ve likely used technology that was birthed, built, or tweaked on its network. The ultra-geeky tech platform is the world’s largest collection of public code and the de facto place where developers now collaborate. Wanstrath describes it for a layperson as Facebook for tech projects. (“You log in, you’re connected to people, but instead of seeing photos of their baby, you see their code.”) Facebook itself has used GitHub. So have SAP, NASA and the White House. Wanstrath launched GitHub in 2008 with Tom Preston-Werner and P.J. Hyett, mostly as a way to see and tweak each other’s ongoing projects. Now it has $350 million in funding, a $2 billion valuation, and 11 million active users. (It has also weathered a sexual harassment claim that led Preston-Werner to step down.) Wanstrath, who was the company’s initial CEO and returned to the role in January 2014, aims to “lower the barrier to entry” and make the site more accessible to those just learning how to code. After all, he says, the future of the world is software, and “that’s what GitHub is all about.”

Chris Wanstrath

In 2012, Sterling, a Stanford-trained mechanical engineer, set out to create toys that teach engineering skills to young girls. Three years later <a href="http://www.goldieblox.com/" target="_blank">GoldieBlox</a>’s colorful building kits are now sold in 6,000 stores worldwide, including Target and Toys “R” Us; they’ll be in Walmart later this year. GoldieBlox-themed books, TV shows, apps, and apparel are in the works, and look for a girl-powered float next month in the Super Bowl of toys, otherwise known as the Macy’s Thanksgiving Day Parade. For Sterling’s part, earlier this year she was invited to the White House, where she was named a Presidential Ambassador for Global Entrepreneurship; and she was recently honored by Gloria Steinem’s foundation for her efforts to get girls interested in STEM.

Debbie Sterling

When Brian Sheth co-founded Vista Equity Partners in 2000 – with Robert Smith, the best man at his wedding – it became one of the very first private equity firms to focus exclusively on software. Not only has the foresight helped make Sheth a billionaire, but it’s also given Vista a leg-up when competing with larger investment firms that are relatively new to the software game. In fact, the San Francisco-based firm claims to have never lost money on a buyout. “In software there are a lot of great technologies, but not as many great business people,” Sheth explains. “We’ve really learned how to put systems in place that improve the companies that grow up around the software.”

Brian Sheth

To paraphrase one of his company’s early ads, this founder is f***ing great. It was only a few years ago that Michael Dubin (and co-founder Mark Levine) set his sights on shaking up the men’s grooming market. The business plan was simple: Sell well-designed men’s razor and blade products, do it online in the form of a membership club, and price them—starting at, yes, a dollar a month—to undercut Gillette (Procter &amp; Gamble) and Schick (Energizer). Dubin gained YouTube fame in 2012 from the hilarious videos that introduced his company. In less than three years he’s turned that early novelty into a legitimate business, with $150 million in funding, 2015 revenues expected to be about the same, and new products including hair gel and peppermint-scented butt wipes. (Yes, really.) Collectively, Los Angeles-based <a href="https://www.dollarshaveclub.com/" target="_blank">Dollar Shave Club</a>—and New York rival Harry’s (see next writeup) are a big reason why U.S. online sales of men’s shaving gear nearly doubled last year to $263 million, and are expected to double again this year. “For a four-year-old company to come in and be right behind Gillette,” Dubin says, “that’s a really meaningful statement of our success.”

Michael Dubin

In the online razor wars, Dubin and Dollar Shave Club came first, but the two companies approach the market differently. By the nature of its name, Dollar Shave Club makes price its biggest differentiator; Harry’s competes on design and engineering, plus a bit of philanthropy. (No doubt a strategy shared with Warby Parker, which Raider co-founded.) To that end, Harry’s owns its own blade manufacturing facility in Germany—one reason why the company has so many employees (and why Katz-Mayfield has picked up some German language skills). “Sometimes we pinch ourselves thinking about having a 600-person team for a company that’s only two years old,” Raider says. His co-founder adds: “We’re going to triple the business this year.” The best measure of the company’s success? Gillette’s launch of its own online subscription shave club.

Andy Katz-Mayfield and Jeff Raider

These three friends, all working in consumer-retail investing, reunited in 2011 to form a private equity firm focused on early-stage consumer retail brands that has quietly racked up win after win. Its most notable was an early investment in Shake Shack before the burger chain went public; ACG remains the fourth-largest shareholder (it owns 6%). But they’ve made a slew of other smart, early bets that all led to successful exits this year: Krave jerky, which became Hershey’s first ever non-candy acquisition; Suja, a cold-pressed juice brand in which Coca-Cola bought a minority stake; and Evol, a maker of healthy burritos that sold to Boulder Brand (owner of Smart Balance) for $48 million. The trio invests $5 to $25 million in young consumer brands that have $5 to $25 million in revenues. Current investments include Babyganics, a maker of safe baby products; two healthy pet-food brands; and California salad chain Tender Greens (ACG co-invested with Shake Shack founder Danny Meyer’s restaurant group). If you’re noticing a pattern, there’s a reason for it: the founders credit their success to a disciplined focus on small consumer companies (mostly food) that follow the trend toward healthy and environmentally sound. As Big Food goes small and hip, ACG wins.

Trevor Nelson, Julian Steinberg, Josh Goldin

Next year marks a decade since <a href="http://fortune.com/unicorns/eventbrite-95/">Eventbrite</a> was formed—and, coincidentally, the 10-year wedding anniversary of Hartz and her co-founder/husband, Kevin. While her significant other has the CEO role, it’s Hartz who has become the internal and external face of the online ticketing platform, now said to be worth more than $1 billion. In addition to advising marketing, PR and customer relations, the former MTV exec spends about one-third of her time on recruiting efforts. The company’s service is now used to organize, promote and sell 8 million tickets per month for a wide range of events—from San Francisco-based indie music shows to Pope Francis’s speech in Philadelphia. But Hartz says her biggest accomplishment is maintaining Eventbrite’s culture even as it has grown (the company recently made Fortune’s <a href="http://fortune.com/best-workplaces-millennials/">100 Best Workplaces for Millennials</a> list, <a href="http://fortune.com/best-workplaces-millennials/eventbrite-com-98/">see company profile here</a>).

Julia Hartz

Since joining brand-licensing firm Sequential in 2012, Shmidman has been buying up an A-list roster of labels, including the clothing lines of Jessica Simpson and Justin Timberlake; Ellen Tracy; and Martha Stewart Omnimedia, which in June Sequential said it would buy for $353 million, its largest deal yet (Stewart will join the board). Shmidman – who was once spoofed on Saturday Night Live’s “Weekend Update” for his business selling iPods preloaded with Jewish content – has grown the company’s total sales at retail from $100 million to roughly $3 billion today.

Yehuda Shmidman

Born and raised in Ghana, Gogo – a Dartmouth engineering PhD – co-founded <a href="http://sproxil.com/" target="_blank">Sproxil</a> in 2009 to fight the scourge of counterfeit pharmaceuticals in Africa. His authentication technology – which relies on basic mobile phones and text messaging – has since been used to verify the source of more than 19 million products. And it’s now being deployed by a number of big brands (think Novartis and Cipla) in six countries – from Nigeria to Pakistan – to find fakes of all kinds: drugs, but also auto parts, underwear and health and beauty products. America’s highest office holders are among Gogo’s fans: Bill Clinton called his company “a remarkable achievement”; in 2013, the Obama administration recognized him as an “Immigrant Innovator” and a “Champion of Change”.

Ashifi Gogo

After losing a bid for Congress in 2010, Saujani – who also served as New York City’s deputy public advocate – founded <a href="http://girlswhocode.com/" target="_blank">Girls Who Code</a> to help underserved girls gain the skills to pursue careers in technology and engineering. Backed by giants like Google and Twitter, it has helped place 10,000 high school-age girls in 34 states in 57 immersion programs where they learn how to code, develop mobile apps, and receive mentoring from women in engineering at companies like Facebook, Goldman Sachs, and AT&amp;T. Saujani raised $500,000 from corporations in 2012; this year that figure will grow to $16 million.

Reshma Saujani

2015 has been the Year of Ronda. The mixed martial arts fighter is undefeated in the ring (many of her bouts last mere seconds) and is said to be the most dominant female athlete in her sport ever; she’s <a href="http://fortune.com/2015/08/05/ronda-rousey-may-be-the-only-mma-fighter-you-can-name-but-the-ufc-still-pays-the-men-more/" target="_blank">earned an estimated $5 million from fighting this year</a> alone. Her influence is broadening fast: She’s hit the big screen three times, with major roles in Furious 7, The Expendables 3, and the Entourage movie, and she’ll play the lead in a forthcoming remake of Road House. She made a surprise appearance with her friend Dwayne “The Rock” Johnson at WrestleMania 31 in March, delighting WWE fans. And she’s inspiring women everywhere with a recent speech about body image that’s been viewed 3.1 million times and was played on-stage by Beyonce in September.

Ronda Rousey

Welcome to Fortune’s 2015 40 Under 40, our annual ranking of the most influential young people in business. For the first time, the list is 100 percent brand new. Read on to meet our disruptors, innovators, rebels (and, yes, unicorns)—and prepare to be inspired. 