It probably shouldn’t surprise anyone when a 92-year-old announces his retirement. And yet the media and entertainment worlds were aflutter this week at the news that the billionaire mogul Rupert Murdoch—the man who was famously never going to retire from Fox News and News Corp—would be stepping down from his chairman roles at both companies. The founder is putting his 50-year-old son Lachlan Murdoch in control of his sprawling empire, which includes some of the world’s most influential and provocative news, opinion, and entertainment outlets.

In a memo to his thousands of employees, the older Murdoch preemptively deflected any suggestion that the move might be connected to his advanced age. “Our companies are in robust health,” he wrote, “as am I.”

But the patriarch’s frail state has been the subject of scrutiny and speculation lately, especially since 2018, when he fell on Lachlan’s yacht during a vacation and required emergency back surgery. Vanity Fair reported earlier this year that the elder Murdoch had been downplaying the severity of complications he suffered after contracting Covid-19.

Investors had been concerned about the patriarch’s occasionally erratic behavior and some setbacks inside his companies, and the market welcomed the news that the polarizing Australian-American, was stepping out of the spotlight.

And Murdoch isn’t the only leader whose age has been discussed extensively recently. The U.S. is heading into an election year with an 80-year-old incumbent presidential candidate, Joe Biden, who’s already the oldest sitting president in history. His likely challenger, Donald Trump, is only three years younger at 77. Outside of government, Warren Buffett, the 93-year-old Berkshire Hathaway founder and CEO, recently reassured investors that the day his named successor steps in is many years off, while his right-hand man and vice chairman, Charlie Munger, is still clocking in for duty at age 99.

How old is too old to lead? It’s a difficult question to answer, and an awkward one. In modern-day America, the elderly are often shunted aside, ignored, or worse. And yet talking about the infirmities that come with age is largely taboo. In a culture where the Puritan work ethic endures, and many successful people define themselves primarily by their job and title, suggesting that someone is too old to work can feel akin to banishing them to an island of the forgotten and the irrelevant.

But like it or not, we need to find the words to have this conversation. As the average U.S. life span has leaped from 68 in 1950 to 76 today; as the average retirement age ticks up to 61 (from 57 in 1991); as older workers contend with dwindling retirement savings and the slow death of traditional pensions; and as Silicon Valley develops elaborate life-extension treatments for those who can afford them, it’s becoming clear that boomers and Gen X workers can and will stay in their jobs far longer than their parents.

At the top tiers of the corporate world, it’s time to get ready for the era of the 100-year-old CEO.

“I’m not going anywhere”

Let’s first acknowledge that in 2023, the possibility of C-suites being filled by centenarians en masse is several years away. Today the average age of a newly appointed S&P 500 CEO is just under 54, while Fortune 500 CEOs average 58. But medical advancements—precision medicine, gene editing, lab-grown organs—may soon make it feasible and even desirable for business leaders to remain in charge into their nineties and beyond.

In the meantime, the over-70 set of industry titans—many of them founders who remain deeply involved in their companies even if they are no longer technically CEOs—are providing a glimpse of what this new world could look like.

Besides Buffett and Munger, there’s corporate raider Carl Icahn, age 87, still running his Icahn Enterprises from Florida; Michael Bloomberg, 81, founder of his namesake financial information and media giant, who recently told employees, “I’m not going anywhere”; Blackstone CEO and cofounder Stephen Schwarzman, 76; Larry Ellison, 78, who remains the CTO of Oracle; and Disney’s “boomerang” leader Bob Iger, who is 72. (George Soros, 92, only gave up control of his Open Society Foundations in June.)

Although some of these legendary leaders have named successors, many aging CEOs have been accused of being unable or unwilling to make space for a new, more diverse generation of leaders. Some founders worry that the companies they built won’t thrive without them.

Indeed, Murdoch’s hesitancy to relinquish his power was evident in his farewell memo to staff: “I will be watching our broadcasts with a critical eye, reading our newspapers and websites and books with much interest, and reaching out to you with thoughts, ideas, and advice,” he wrote. “When I visit your countries and companies, you can expect to see me in the office late on a Friday afternoon.”

Beyond their personal preference about when to retire, aging CEOs face a moral quandary: What happens to a company’s performance and its employees if a CEO has a stroke, or suffers any number of other potentially debilitating events?

Aven if a CEO is perfectly healthy, their lingering presence at the top can be corrosive: It can demoralize top talent who see no pathway to the chief job.

“It is profoundly selfish to stick around past your sell-by date,” Jim Schleckser, head of the CEO Project, an executive coaching company, told CNBC.

Accommodate and empower older leaders

No one is suggesting that today’s aged business leaders are all suffering from serious cognitive decline. Aging today is far from a singular experience. For many, every passing year brings declines in cognition and physical mobility; for others, the changes are barely detectable. In fact, many researchers and aging experts argue that fretting over anyone’s age is both alarmist and ageist.

Mo Wang, a professor at the University of Florida’s Warrington College of Business, told Fortune he sees no reason to suggest an upper age limit for CEOs. The professor points out that decades of data have shown that at an individual level, age is not correlated to job performance. “Whenever people tell you, ‘Older people, they are less competent,’ that’s a stereotype, but that’s not true,” he says. In fact, he adds, “being older actually sets up the conditions for good leadership.”

Older adults tend to be warmer, friendlier, and more empathetic than younger people. By the time people reach their later years, they’re also generally more content, which gives them emotional stability, says Wang.

As we grow nearer to the end of our lives, most people ponder what they’ll be leaving for future generations beyond material goods. What values will they instill? This concern can influence a person’s leadership style and the degree to which it is deemed “transformational.”

But the most intuitive defense of older CEOs is that age confers experience and lessons learned: wisdom. Older leaders have built a deep virtual database of playbooks to tap when a problem arises or when a company faces a new challenge, says Wang. We tend to think of a leader as someone who is good at taking charge and being a decision-maker, he adds, and older leaders have more practice in making tough calls.

Chip Conley, author of Wisdom at Work: The Making of a Modern Elder, sees older employees as “wisdom workers”—a grade above the “knowledge worker.” Human wisdom is set to become more critical than ever, he says. It certainly cannot be programmed into an AI large language model.

Conley proposes that older and younger employees mentor each other, to compensate and enhance each other’s strengths and weaknesses. As early as age 45, people can start to experience a decline in their ability to remember new information, and processing information quickly becomes more challenging in mid-life. However, the brain compensates for these transformations with a form of mastery: Over time, some of our skills are “crystallized” as second nature.

Older workers should be valued for their wisdom and crystallized abilities, Conley says, suggesting that older and younger workers can engage in two-way mentoring, as “menterns”—each both mentor and intern. A junior employee can keep a mentee abreast of changing technology and other trends that impact the world of work, while the older employee shares the perspectives they’ve gained over a lengthy career.

Vincent Stanley, 71, the “director of philosophy” at the outdoor apparel company Patagonia, says healthy companies need a mix of younger and older leaders. Older leaders bring wisdom and tolerance, particularly during a crisis, but he adds: “You also don’t want a bunch of 70-year-olds sitting around a table without people who are hungry and quick.”

Younger people—today’s Gen Zs and millennials—see the world differently, says Stanley, a former head of sales and marketing at Patagonia and the author of The Future of the Responsible Company. “They’ve gone through Trump, they’ve gone through climate change, they’ve gone through Greta Thunburg,” he tells Fortune. “They’ve had Earth Day their whole lives. Their attitudes are very different about the world than people who started working in the nineties.”

There’s no data to prove that the silver-haired are better or worse than fresher-faced leaders. But some studies suggest that working for an older manager is preferable to toiling for a greener one. In 2019, global surveys of more than 10,000 managers showed that younger managers were seen as having a more “self-centered approach” to managing a team.

In 100 CE, Plutarch—then about 70—described the flip side, arguing that older leaders tend to demonstrate selflessness: “The elder speaks soothingly and, without finding fault, instructs those who are mistaken in their judgments, fearlessly praising those who get things right, and willingly losing political contests,” he wrote. “Oftentimes the elder forgoes the chance to come out on top, so that others may grow and gain confidence.”

A study by the leadership consulting firm Spencer Stuart suggests that unceremoniously dumping a CEO at an arbitrary age could mean dethroning talented executives who still have a lot to contribute. Although the data show that CEOs can fall into a “complacency trap” in years six to 10 of a long tenure, the consultants found that those who stayed on beyond that period experienced their “golden years” of stellar performance.

Jim Citrin, head of Spencer Stuart’s North American CEO practice and one of the study’s authors, says boards ought to stop using age as a marker of capability—full stop. “Use passion, energy level, health, vitality, adaptability, motivation,” he says.

Leadership research supports his proposition. Having a “growth mindset”—being eager to learn and experiment, and quick to change what isn’t working—is an important predictor of effective leadership. And the young do not have a lock on this trait, just as the old are not the only ones vulnerable to poor health.

In some cases, technology and other support systems can make up for the symptoms of decline that eventually affect every aging human. The older CEO who is slightly hard of hearing might turn to nearly invisible hearing aids or inconspicuous earbuds, for example. Scheduling online meetings means executives can forgo some physically grueling trips. One day, AI tools—already shown in studies to help brain injury victims—might allow leaders to quickly revisit information they need, essentially outsourcing their memories. (For now, an executive assistant or deputy can perform this role.)

A “beautiful exit”

But gadgets and crack executive teams can also become accidental enablers of a leader’s addiction to power.

When leaders show signs of decline while still on the job, it’s often hard for others to do anything about it, especially when it comes to founders with a deep emotional connection to their companies. “All you can do is inspire a conversation,” one leadership coach tells Fortune, “because at the end of the day, it’s their company, their money, their choice.”

After decades spent chasing and holding on to power, it’s understandably hard hard to give up, says the Dutch management scholar Manfred Kets de Vries. “We’re status-seeking animals, and when you are the CEO, consciously or unconsciously people look up to you; they tell you, ‘You’re the greatest, you’re fantastic.’”

We now know that romantic partnerships and close relationships with family members or friends are key to happiness at any life stage. But driven CEOs sometimes find that they have neglected other parts of their lives over their decades establishing their dominance in business says Kets de Vrie. Many CEOs keep themselves extremely busy, because when they’re not busy, they get depressed, he says. Work may be the only place where they find a sense of belonging, says Kets de Vries. “Why let go?”

But wise is the older CEO who recognizes when age is denting their performance, or who chooses to make the most of the time they have left and enjoy the spoils of a life of hard work. Kets de Vries calls this a “beautiful exit”—one that forges a lasting impression of a leader.

That’s what the 76-year-old Republican Sen. Mitt Romney of Utah managed to pull off when he announced in September his plans not to seek reelection. “I think it’s time for guys like me to get out of the way,” Romney told reporters. Of the leaders coming up behind him, he said, “They’re the ones that need to make the decisions that will shape the world they will be living in.”

It remains to be seen what Romney or Murdoch will do with their free time in retirement. The standard off-ramp for CEOs and other C-suite leaders involves joining one or a handful of corporate boards. Some older leaders may decide they want to spend more time with family; the arrival of grandchildren can be a game changer, says Kets de Vries. A hobby such as fly-fishing can become a new outlet for ambition. A humanitarian project or class to teach can offer a new way to engage and influence the world.

Eventually, Kets de Vries says, companies should support offboarding as they do onboarding: with training and ongoing coaching. But to get there, our culture first needs to get over the tendency to see geriatric issues as gloomy, while fawning over the wonders and beauty of youth.