The same day that Gayle and Mark Arrowood retired from their jobs at a Department of Energy lab, they drove to Sun Valley, Idaho, to start their next chapter: ski-resort bartending. Mark had a shift that very night.

Their previous roles had been intense: Over multi-decade careers, Mark had worked his way up from a janitor to a manager, and Gayle had gone to night school and become a scheduler for the lab’s projects. Because of how far away they’d lived from the lab, they had needed to wake up at 3 or 4 a.m. to make it in on time. They’d enjoyed aspects of the work, but their days had also been filled with office politicking and an itch to work for the next promotion.

The married couple had started working at the ski resort on weekends years ago, after they’d decided to go to a job fair on a whim. They ended up loving their co-workers and customers, so when they retired in 2017, they saw no reason to stop; although their old jobs could be draining, they actually looked forward to their shifts at the bar. “We were desk jockeys, secretarial admin, management, and now we’re hucking ice and cases of wine. We were six-figure employees, and now we’re making minimum wage,” Gayle told me. “And we love it.”

The Arrowoods’ transition happened amid a strange economic shift in the United States: Over the past 20 years, at the same time as labor-force-participation rates have dropped for younger people, they’ve risen among older adults. Some are simply postponing their exodus from work. But for many, the line between employment and retirement is muddier. In the past month, 13 percent of retired Americans worked for pay, which could mean a one-off gig or a dedicated part-time job. Others are “un-retiring” after a period away.

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For far too many, the decision to continue working is driven by financial necessity—an especially concerning reality given how few healthy years the average poor American has left by the time they reach retirement age. But this trend doesn’t reflect only people who can’t afford to quit. According to one 2014 survey, 80 percent of semi-retirees say they’re employed because they want to be; working after retirement is actually more common among workers with higher socioeconomic status. Though some of them might appreciate the extra income, many seem to also find these jobs enjoyable and fulfilling.

The idea of a retirement purposely filled with work might seem dismal—proof that we’ve prioritized achievement over happiness for so long that we can’t even stop in our 60s. But there might be a less pessimistic way to look at those who actively choose semi-retirement. After all, they represent a rarity in the labor market: the truly empowered worker. Examining what they get from the jobs they don’t need could illuminate what a career can offer the rest of us, helping us reimagine our relationship to work long before it’s time to retire.

At first glance, lazing on the beach might sound more appealing than the Arrowoods’ bartending gig. But days can be long and boring without work to fill them. Joe Casey, who coaches people through retirement, told me that many of his clients are scared of what will come after they leave their career. Most jobs provide structure, socialization, and even basic physical activity. “When you work, there’s a reason to get up in the morning,” Nancy K. Schlossberg, a retirement expert and professor emerita of counseling psychology at the University of Maryland at College Park, explained. When people lose the community and challenge their work provided, their health—both physical and cognitive—can suffer. Of course, there are other ways to keep your brain and body healthy, such as volunteering or pursuing a hobby. But lots of jobs can be surprisingly good for you.

Crucially, the jobs many semi-retirees choose aren’t as demanding as the careers of their youth—or at least not in the same way. Take the Arrowoods: At the ski resort, they have no desire to move up the management ladder. They work on a seasonal schedule that gives them plenty of vacation time to take advantage of last-minute flight deals. They enjoy perks such as free ski passes, and they consider themselves “surrogate grandparents” to their co-workers’ kids. Maybe most importantly, knowing they could quit at any time gives them a sense of autonomy. “This isn’t a job of necessity,” Mark told me. “This is a job of desire.”

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The experts I spoke with told me that semi-retirees tend to look for roles that grant a sense of purpose, the ability to keep learning, and, perhaps more than anything, flexibility. “Most jobs come as full-time, five-day week, 40 hours at least, or more—typically more. And they don’t want to work that way. They want to work differently,” Phyllis Moen, a sociologist at the University of Minnesota, told me.

Those lucky enough to be able to do so might use this period to pursue niche passions, fulfill lifelong dreams, or find new ones that their younger self would never have thought of. Reporting this story, I heard about an engineer who got involved in the National Park Service, a congressional researcher who trained as a massage therapist, and the vice president of a manufacturing-equipment company who started hawking hot dogs at baseball games. Others might just scale back on hours at their current jobs or step away and come back later. In fact, a full 40 percent of employed people 65 and older were previously retired. But even a temporary retirement, rather like a sabbatical, can give people time to recharge and reevaluate what they want from a career, if they want one at all. If they return—even to a traditionally ambitious role—it might not be because they have to, but because they want to.

The types of flexible gigs that many retired people look for have, historically, been hard to come by. If they weren’t, perhaps even more people would be semi-retired: One study found that about half of retirees would consider returning to work if a good opportunity came their way. But the current tight labor market is forcing some employers to be less rigid. Other trends, such as the push for a four-day work week and the popularity of remote work, can also make employment more appealing to semi-retirees. And companies that are generous to older employees tend to help younger workers too. In her research on age-friendly workplaces in the Twin Cities, Moen found that when companies were more open to accommodating different scheduling needs or giving workers chances to learn, “it opened up opportunities for everyone.”

Of course some of the benefits of semi-retirement are available only to certain people—those who can afford to work in the way they actually want. And part of the magic of semi-retirement is its role as a capstone to a long career. When I asked the Arrowoods whether they regretted their previous work, both said no; those jobs got them where they are today. They got to be recognized for their achievement—and to bolster their savings—before they turned to a role that was simply fun.

As today’s young Americans stare down a future in which it may be common to work 60 years or more before retiring, they’d do well to figure out what they actually enjoy in a job. And plenty of them, it seems, are trying to do just that. More than 50 million people in the U.S. quit their jobs in 2022, many in search of something better—less taxing, more fulfilling, less all-consuming. Even those still striving, then, to create a career they’re proud of might look to semi-retirement as a model of what work could look like—flexible, meaningful, and with the potential for reinvention at any age.