Members of the baby boomer generation, who in their youth proclaimed, “Don’t trust anyone over 30,” would rather not be segregated with people their own age as they grow older.As they watch their elders living longer—to age 83 on average in Singapore, 81 in the U.K., and 79 in the U.S., with more people becoming centenarians each year—­boomers are rejecting the notion that they should spend their later years devoted to leisure, isolated from the experiences of younger people. Growing numbers of U.S. ­boomers—currently 55 to 73—are working beyond the traditional retirement age, going back to school, and choosing to age in place in familiar neighborhoods instead of moving to senior communities. As a result, they’re connecting with people of diverse ages.

“For the first time in history, there are multiple generations alive together for long stretches of time, and that’s creating more contact and similarities among older, middle-aged, and young people,” says Laura Carstensen, a Stanford psychology professor and director of the Stanford Center on Longevity. “When you have people in their 70s sitting next to kids in their 20s in classrooms and workplace cubicles, you get more creativity and productivity, research shows, and less age stereotyping.”

A 21-year-old today is more likely to have a living grandmother than her counterpart a century ago was to have a living mother. And the 21-year-old and her 70-year-old grandmother may both be employed; just as the young need income to support themselves, many older people lack sufficient savings to fund two or three decades of retirement.

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Sig Van Raan has divided his time between writing and nonprofit work since he retired seven years ago from a 40-year career as a psychotherapist. He’s written a play and a children’s book, and he’s a director at the Yard, a contemporary dance and performance center on Martha’s Vineyard, Mass., where he lives half the year. A benefit to these activities, which he cherishes: Van Raan, 73, gets to collaborate with writers, actors, dancers, and volunteers of many different ages and backgrounds. He also plays on Sunday mornings in the island’s Chilmark Softball League, whose members—­doctors, carpenters, fishermen, scientists, students, and others—range in age from 14 to 84. “It’s a strongly supportive group, who especially cheer when an older guy gets a good hit or makes a good play,” he says. “It’s competitive, and it’s fun.”

Generational intermingling is most pronounced in the workforce. Companies today typically employ four or five generations of workers. Although millennials, in their 20s and 30s, are the largest cohort, baby boomers are the only group with a growing participation rate. About 27% of 65- to 74-year-olds had full- or part-time jobs in 2016; by 2026, 30% are expected to be employed, according to the Bureau of Labor Statistics.

Industries with skills shortages and large numbers of employees approaching retirement age, such as accounting, health care, and manufacturing, are trying to retain older workers, sometimes by offering flexible or part-time schedules. That’s the case at Allina Health in Minneapolis, where one-third of about 29,000 employees are 50 or older and where Chief Executive Officer Penny Wheeler tells staff, “We need you for a marathon, not a sprint.” And at Huntington Ingalls Industries Inc. in Newport News, Va.—the nation’s largest military shipbuilder—many workers, one-third of whom are in their 50s or older, work on multi­generational teams.

“Employers know they need to blend employees of many ages to meet their talent needs,” says Andrew Scott, an economics professor who studies longevity at London Business School and the co-author of The 100-Year Life. “Luckily, there’s a generation of older workers who are better educated and more physically fit than those who preceded them,” he says. “Plus, the human skills most needed today—understanding consumers, teamwork, and leadership—play to older workers’ strengths.”

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Higher education, long a bastion of age segregation, is also becoming more multigenerational. Harvard, Notre Dame, Stanford, the University of Minnesota, and the University of Texas at Austin have programs aimed at helping people over 50 change careers or find new uses for their experience. The older students take most of their classes alongside undergraduate and graduate students.

Other efforts seek to connect the elderly and very young. Some preschools in Singapore are located within senior centers, and younger Singaporeans are teaching technology to older people. The city-state has allocated billions of dollars to create kampongs, or villages, for all ages and promote a variety of intergenerational interactions.

In the U.S. more than 100 organizations bring together elders and children, says a 2018 report by the nonprofit Generations United and the Eisner Foundation, which invests in programs that connect generations. In Miami a senior center to which grandparents often brought their grandchildren has become the Rainbow Intergenerational Child Center. Such programs combat the loneliness that’s problematic for many seniors and young people.

More of this is likely as countries around the world become more old than young. Globally, more people are over 65 than under 5 for the first time; in the U.S., more people are older than 60 than under 18. Some fear this change, which will become more pronounced in coming decades, will trigger conflict between generations over diminishing resources.

It doesn’t have to be that way, says Stanford’s Carstensen, “if we exploit longer lives to have more multigenerational contact in ways that benefit everyone.” She’s seen this in her psychology lab, where older professors and younger students regularly exchange ideas, with little focus on chronological age. “Every once in a while, someone says, ‘I’m turning 21’ or ‘I’m turning 60,’ and I’m surprised, because I haven’t thought about how old they are, just what they know and do.”

Read more: Adapting homes and lives to a growing population

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