When you’re a mover and shaker, coasting isn’t really an option.

That’s certainly true of recent members of Fortune’s annual 40 Under 40 list. In the past couple years, these innovators have experienced some incredible highs and very real lows. From business triumphs, to prominent new positions, to feuds and scandals, their collective experiences could fill volumes.

Here’s a snapshot of what 12 recent alumni of Fortune’s 40 under 40 are up to now.

Adam Neumann (2015)

The WeWork co-founder and CEO topped the list last year, thanks in large part to the company’s aggressive expansion. The growing streak hasn’t stopped: WeWork, which provides communal workspaces, now has 112 office locations in 33 cities and is valued at $16 billion.

But the past few months have been rough for the company. In July, a leaked document revealed that WeWork had cut its 2016 forecast by 78%, its revenue estimate by 14%, and increased its projected negative cash flow by 63%. Meanwhile, WeLive—locations that serve as both office space and residences for members—is off to a slow start. How Neumann will handle pressure to maintain the company’s explosive growth remains to be seen, but he’s definitely one to watch in the year ahead.

Key Speakers At The TechCrunch Disrupt Summit Adam Neumann, co-founder and chief executive officer of WeWork. Bloomberg — Getty Images

Jared Kushner (2015)

Since the real-estate businessman and investor was featured on Fortune’s 40 Under 40 list last year, he’s stepped into an even brighter spotlight. Kushner, who took the reins from his father Charles as CEO of Kushner Companies in 2008, happens to have a famous father-in-law: Donald Trump, i.e. the Republican Party nominee for President of the United States. Despite having little previous political experience, Kushner is an influential, trusted advisor to Trump and was reportedly instrumental in the ousting of former campaign manager Corey Lewandowski. As we hurtle towards the election in November, expect to hear more about him.

COMEDY CENTRAL Roast Of Donald Trump - Backstage Jared Kushner, Ivanka Trump and Donald Trump. Jeff Kravitz — FilmMagic

Elizabeth Holmes (2014)

Of all the alumni on this list, Elizabeth Holmes’ change in circumstance is the most pronounced. When the founder and CEO of blood analytics company Theranos was featured on Fortune’s 40 under 40 list in 2014, she was feted as a genius and a visionary. A mere two years later, she has become a symbol of Silicon Valley’s dark underbelly.

Holmes began to lose control of her tightly spun narrative last summer, with the publication of a damning Wall Street Journal article that poked holes in the effectiveness of Theranos’ core technology. Since then, the company has continued to unravel—its blood-testing technology has been discredited and federal regulators banned Holmes from owning or operating a medical laboratory for at least two years. Silicon Valley’s golden child is now officially a cautionary tale.

Interviews On The Sidelines Of Vanity Fair New Establishment Summit Elizabeth Holmes, founder and chief executive officer of Theranos Inc. David Paul Morris — Getty Images

Taylor Swift (2015)

Despite not releasing a new record since appearing on Fortune’s 40 under 40 last year, Taylor Swift continued to dominate the headlines. From a breakup with DJ Calvin Harris, to a public feud with Kim Kardashian and Kanye West, to her intense, but short-lived, social-media lovefest with actor Tom Hiddleston, Swift captivated our attention. Yes, some of the publicity turned sour in tone, but it also proved the pop star knows how to make a continued splash. Her next album is rumored to launch this fall; when it does, we can expect Swift to whip up the appropriate frenzied coverage (particularly if it includes songs about her latest string of high-profile relationships).

Taylor Swift '1989' World Tour - Sydney Taylor Swift performs during her ‘1989’ World Tour at ANZ Stadium on November 28, 2015 in Sydney, Australia. Mark Metcalfe — Getty Images

Related: Here’s the Brilliant Advice That Fortune’s 40 Under 40 Live By

Jason Robins (2015)

The last 12 months have been eventful ones for Jason Robins, who made Fortune’s list last year. As CEO of the daily fantasy sport site DraftKings, he’s faced steep competition from rival site FanDuel while clashing with officials in a number of states, most notably New York Attorney General Eric Schneiderman, who sued to shut the startup down in the state.

Since then, the company has worked to create new procedures and controls to pacify regulators. It also just raised more than $150 million in funding (albeit at a lower valuation)—proof that Robins’ quest to turn DraftKings into a sustainable business isn’t over yet.

TechCrunch Disrupt SF 2016 - Day 1 Draft Kings CEO Jason Robins. Steve Jennings — Getty Images for TechCrunch

Marissa Mayer (2012, 2013, 2014)

It’s been a tough year for Marissa Mayer. But by now the Yahoo CEO, who topped Fortune’s 2013 list and was included in 2012 and 2014, is used to operating in hot water. Since taking the reins at Yahoo in 2012, she’s faced a constant barrage of criticism over her handling of the company. At this point, much of it is warranted: Mayer’s turnaround strategy, which involved a series of expensive acquisitions, failed to produce health financials. After an awful fourth quarter in 2015, Mayer bowed to investor pressure to disband the company and in July, Yahoo sold its core internet assets to Verizon for $4.8 billion. While Mayer’s next act is unclear, one thing is certain: she won’t be able to add “Yahoo’s savior” to her resume.

Marissa Mayer Delivers Keynote At Yahoo Mobile Developers Conference Yahoo! President and CEO Marissa Mayer. Stephen Lam — Getty Images

David Chang (2012)

The outspoken restaurateur, who was appeared on Fortune’s 40 under 40 list in 2012, continues to redefine what it means to be a chef in America. You’d think Chang’s existing projects—high-end restaurants in New York City, Sydney, and Toronto, a handful of bakeries, bars, and a quarterly food magazine—would be enough to occupy his time, but no. In the past few years, Chang has added new projects to his already (very) crowded plate, including Maple, a food delivery service and app, and Fuku, a shop dedicated to fried chicken, all while overseeing a well respected (and reviewed) culinary empire.

David Chang's Momofuku and Christina Tosi's Milk Bar open in CityCenter soon David Chang poses at Momofuku. The Washington Post — Getty Images

Hayley Barna & Katia Beauchamp (2013)

A lot has changed since Hayley Barna and Katia Beauchamp appeared on Fortune’s 40 under 40 list in 2013. For one thing, the co-founders (and then co-CEOs) of beauty subscription service Birchbox no longer work together. Barna left the company last year, and is now a partner at the venture capital firm First Round Capital. Meanwhile, Beauchamp is still CEO, a role that’s grown more challenging. The company, which now competes with a number of beauty subscription upstarts, struggled to raise new capital but recently secured a $15 million lifeline as it works towards profitability.

Key Speakers At The TechCrunch Disrupt Summit Katia Beauchamp, left, and Hayley Barna, founders of Birchbox Inc. Bloomberg — Getty Images

Ben Rhodes (2014)

As deputy national security advisor for strategic communications for President Obama, Ben Rhodes is also a former aspiring novelist. So it’s somewhat ironic that the Fortune 40 under 40 alum became the subject of a heated narrative when he was profiled in The New York Times. Everything about the piece was controversial—from Rhodes’ quotes, to his involvement in the United States’ nuclear deal with Iran, to the author’s intentions—spawning various think pieces about the state of politics, the media, and the country in general.

Deputy National Security Advisor Ben Rhodes And White Deputy Press Secretary Eric Schultz Brief The Media White House Deputy National Security Advisor Ben Rhodes. Darren McCollester — Getty Images

Josh Tetrick (2014)

Since making Fortune’s 40 under 40 list in 2014, Josh Tetrick has found himself in a few sticky situations. First, it was a bizarre battle with the U.S. egg industry. To backtrack: Tetrick is the founder and CEO of Hampton Creek, a company that makes eggless mayo, cookie dough, and salad dressing. After attracting cash ($120 million in venture funding to date), high-profile cheerleaders (including Bill Gates and Yahoo co-founder Jerry Yang), and a lot of publicity, the company received something less favorable: a warning letter from the FDA. The agency wasn’t pleased the startup was calling its vegan spread Just Mayo (mayo, the FDA argued, must contain eggs).

After some hard lobbying from Hampton Creek and a few revelations — most notably, that executives of the US egg industry and an official from the US Department of Agriculture had brainstormed how to take down the company via email—the agency backed down. Just Mayo was allowed to remain Just Mayo.

But Tetrick’s problems aren’t over. The Securities and Exchange Commission is looking into whether Hampton Creek inflated revenue by purchasing its own products. This news comes at a precarious time for the company, which is in the process of raising new funding at a $1 billion valuation.

Hampton Creek Foods Inc. Chief Executive Officer Josh Tetrick Interview Josh Tetrick, chief executive officer of Hampton Creek Foods Inc.Bloomberg — Getty Images

Jack Dorsey (2012, 2013, 2014)

A multiple-time 40 under 40 alum, Dorsey is now the CEO of two high-profile Silicon Valley companies: Square and Twitter. The former, a payments technology company that Dorsey founded in 2009, went public late last year. Twitter, which has been publicly traded since 2013, has gone through a series of CEOs as it struggles to attract new users. Dorsey has a tumultuous history with the company—a co-founder, he served as CEO, before being booted out in 2008—and was reinstated as chief executive just under a year ago. Recently, there are rumors that Twitter may be considering a sale. Whatever the company’s next step, expect Dorsey to be front and center.

Square Inc. Begins Trading On The NYSE Following IPO Jack Dorsey, chief executive officer of Square and Twitter.Bloomberg — Getty Images