If you’ve ever lost a glove somewhere on the streets of New York City, there’s a chance it’s found an unusual second life at the New York headquarters of OXO—the global housewares manufacturer. Enter the company’s open loft-style dining hall, and you’ll see a large white wall featuring hundreds of gloves, neatly organized in rows. Pinned beneath each glove (or pair) is a tag that tells the story of when and where the glove was found, and who did the finding.

As part of a unique company ritual, OXO employees are encouraged to collect the misplaced and forgotten gloves of New Yorkers and add them to the wall. OXO says that focusing on the “meaning of gloves” serves as a symbolic reminder of the company’s most important value principle: The universal design of their products fitting comfortably in the hands of all their customers.

Research suggests that these sorts of quirky company traditions really can help affirm a company’s core values and promote a sense of collective workplace culture. But they can also come with a downside—which means that companies need to be very careful about how they implement their rituals.

Anthropological research, which typically looks at religious and cultural practices, shows that rituals lead to a host of positive social outcomes for groups. They help to rally people around a shared value, unify their experience, and forge stronger individual relationships. We’re now beginning to understand that the power of ritual also helps bond sports fans, college students, and coworkers.

But there’s a catch. In organizations, as well as in society, there are in-groups and out-groups. Teams and divisions may have their own bonding rituals, from a weekly lunch to a quarterly retreat, from which other employees are excluded. When a company’s teams begin to engage in their own specific rituals, what does it mean for company culture as a whole?

To find out, my co-authors and I investigated this question in a series of four experiments. Specifically, we tested the prediction that even small rituals are enough to bias people to favor their own in-groups over out-groups.

Even small rituals are enough to bias people to favor their own in-groups over out-groups.

In the first experiment, 100 students were assigned to estimate the number of dots in a series of images once a day, over the course of a week. Before estimating the dots, half of the students were told to perform a ritualistic sequence that involved raising their hands over their heads, bowing their heads, and opening and closing their eyes. They were told the ritual was part of an ancient cultural practice. At the end of the week, participants came into the lab and played a game involving money. The results showed that participants who had practiced the ritual entrusted more money to people with whom they had shared the same ritual, and less money to members with whom they did not share the same ritual.

Next, we wanted to understand the effects of different types of ritual on bias. For instance, why do many group rituals involve considerable amounts of effort or pain? We predicted that elaborate rituals would be more likely than simple rituals to promote bias against the out-group. After all, shared effortful experiences—from boot camp to hazing rituals—seem to bring people together. Our guess was that more exertion would generate even more bias against the out-group.

To test this theory, we randomly assigned 90 participants to one of three conditions: performing an elaborate ritual for a week, performing a simple ritual for a week, or not doing a ritual at all. As before, when participants came into the lab after the week, the ones who had completed the elaborate ritual were the most biased in how they entrusted money to others. Effort or pain in ritual, it seems, is a built-in mechanism that serves to strengthen group ties—but at an expense to those who don’t belong.

So why is it that performing a ritual seems to make us more likely to separate the people around us into in-groups and out-groups? In another experiment, we asked subjects to participate in the same week-long procedure. Then participants’ brain processing was tracked using electroencephalography (EEG) while they observed in-group and out-group members receive feedback on a task.

Members of in-groups processed a reward for a fellow group member in the same way they would a reward for themselves.

We found that participants in the ritual condition responded to rewarding feedback to in-group members in the same way they would track rewards to themselves. They processed a reward for a fellow group member in the same way they would a reward for themselves. But they responded to punishing feedback to out-group members in the same way they would track rewards to themselves: a punishment to an outsider is a reward for them. The Germans, of course, have a word for this phenomenon – schadenfreude.

Our findings suggest that as company rituals become more commonplace, it’s important for organizations to think about the possible negative consequences of workplace culture traditions. This may be particularly important for companies with organizational structures made up of multiple departments.

Existing conflicts between two teams could be made worse by designing team-specific rituals. For instance, a happy hour tradition that involves only the sales team could weaken ties between this group and the IT team.

This thinking also aligns with the contemporary management practices involving efforts to break down business silos. Instead, to mitigate conflict, we recommend creating a workplace ritual that is inclusive of multiple teams and that helps emphasize the shared values between them. Rituals are great—but they work best when they’re a tradition that everyone in the company can get behind.