Scan the newspaper headlines, or switch on cable news for a few minutes, and it’s easy to conclude that we are living through harsh, mean, divisive times. But a recent column in the Washington Post reminded me of a truth that is even easier to overlook: Just as bad behavior tends to spread, so too does good behavior. Kindness, it turns out, is contagious. The column highlighted the work of Stanford psychologist Jamil Zaki, who documents what he calls “positive conformity.” In his research, “participants who believed others were more generous became more generous themselves.” This suggests that “kindness is contagious, and that it can cascade across people, taking on new forms along the way.”

Zaki’s insight is vital for improving society, but it applies to companies too. Almost every leader I know wants his or her colleagues to go above and beyond normal standards of service, to impress customers with their kindness. Many of these leaders also believe that achieving this goal is largely a matter of policies and procedures — kindness as a directive. Actually, the way to unleash kindness in your organization is to treat it like a contagion, and to create the conditions under which everybody catches it.

Consider one instructive case study. I recently immersed myself in the customer-service transformation of Mercedes-Benz USA, the sales-and-service arm of the German automaker. When Stephen Cannon became president and CEO of Mercedes-Benz USA, he recognized that success was about more than just his vehicles. It was about how much the people who sold and serviced the cars cared and how generously they behaved. “Every encounter with the brand,” he declared, “must be as extraordinary as the machine itself.” And almost every encounter with the brand, he understood, came down to a personal encounter with a human being in a dealership who could either act in ways that were memorable, or could act the rote way most people in most dealerships act.

Cannon also understood that if he wanted to influence the behavior of more than 23,000 employees at Mercedes dealerships, there was no rule book he could write to engineer a culture of connection and compassion. Instead, he had to convince dealers and their staffers to join a grassroots “movement” that treated kindness like a contagion.

“There is no scientific process, no algorithm, to inspire a salesperson or a service person to do something extraordinary,” Cannon told me. “The only way you get there is to educate people, excite them, incite them. Give them permission to rise to the occasion when the occasion to do something arises. This is not about following instructions. It’s about taking a leap of faith.”

Over the last few years, this leap of faith unleashed all sorts of everyday acts of kindness. There was one dealer who’d closed a sale and noticed from the documents that it was the customer’s birthday. So he ordered a cake, and when the customer came in to pick up the car, had a celebration. Then there was the customer who got a flat tire on the way to her son’s graduation. She pulled into a Mercedes dealership in a panic and explained the problem. Unfortunately, there were no replacement tires in stock for her model. The service manager ran to the showroom, jacked up a new car, removed one of its tires, and sent the mother on her way. “We have so many stories like this,” Cannon says. “They’re about people going out of their way because they care enough to do something special.”

There was another ingredient to the Mercedes-Benz contagion. It’s more natural for front-line employees to show kindness towards customers, it turns out, if they are motivated by genuine pride in what they do. Harry Hynekamp, a 15-year veteran of Mercedes-Benz USA, became the first-ever general manager for customer experience. As Hynekamp and his team traveled across the country, they discovered that “pride in the brand was not quite as strong as we thought, the level of engagement with the work not as deep as we thought.” What really shocked them is that nearly 70 percent of front-line employees had never driven one of the cars outside the dealership lot. They’d repaired them, ordered parts for them, but they’d never been behind the wheel on the open road.

How could people take genuine pride in the brand, Hynekamp wondered, if they’d never themselves experienced the thrill of driving a Mercedes-Benz vehicle? So he created a program through which all 23,000 dealership employees got to drive a new Mercedes-Benz for 48 hours. The company put close to 800 cars in the field, at a cost of millions of dollars. Employees often timed their turns behind the wheel to correspond with important events — picking up grandma on her 90^th birthday, driving a daughter and her friends to a Sweet 16, bringing a newborn baby home from the hospital. The participants took photos, made videos, and in one case, even wrote a rap song, to chronicle their 48 hours.

“The reactions were out of this world,” Hynekamp told me. He created an internal website to collect and share the stories. “Sure, people got to know the cars very well. But the biggest piece was the pride piece.”

This bottom-up, peer-to-peer commitment to customers at Mercedes-Benz USA is a powerful case study in service transformation. It’s also a reminder for leaders in all sorts of field: You can’t order people to be kind, but you can spark a kindness contagion.