What Google Learned From Its Quest to Build the Perfect Team

New research reveals surprising truths about why some work groups thrive and others falter. ## here story Julia Rozovsky Like most 25-year-olds, Julia Rozovsky wasn’t sure what she wanted to do with her life. She had worked at a consulting firm, but it wasn’t a good match. Then she became a researcher for two professors at Harvard, which was interesting but lonely. Maybe a big corporation would be a better fit. Or perhaps a fast-growing start-up. All she knew for certain was that she wanted to find a job that was more social. ‘‘I wanted to be part of a community, part of something people were building together,’’ she told me. She thought about various opportunities — Internet companies, a Ph.D. program — but nothing seemed exactly right. So in 2009, she chose the path that allowed her to put off making a decision: She applied to business schools and was accepted by the Yale School of Management.

When Rozovsky arrived on campus, she was assigned to a study group carefully engineered by the school to foster tight bonds. Study groups have become a rite of passage at M.B.A. programs, a way for students to practice working in teams and a reflection of the increasing demand for employees who can adroitly navigate group dynamics. A worker today might start the morning by collaborating with a team of engineers, then send emails to colleagues marketing a new brand, then jump on a conference call planning an entirely different product line, while also juggling team meetings with accounting and the party-planning committee. To prepare students for that complex world, business schools around the country have revised their curriculums to emphasize team-focused learning.

Every day, between classes or after dinner, Rozovsky and her four teammates gathered to discuss homework assignments, compare spreadsheets and strategize for exams. Everyone was smart and curious, and they had a lot in common: They had gone to similar colleges and had worked at analogous firms. These shared experiences, Rozovsky hoped, would make it easy for them to work well together. But it didn’t turn out that way. ‘‘There are lots of people who say some of their best business-school friends come from their study groups,’’ Rozovsky told me. ‘‘It wasn’t like that for me.’’

Instead, Rozovsky’s study group was a source of stress. ‘‘I always felt like I had to prove myself,’’ she said. The team’s dynamics could put her on edge. When the group met, teammates sometimes jockeyed for the leadership position or criticized one another’s ideas. There were conflicts over who was in charge and who got to represent the group in class. ‘‘People would try to show authority by speaking louder or talking over each other,’’ Rozovsky told me. ‘‘I always felt like I had to be careful not to make mistakes around them.’’

So Rozovsky started looking for other groups she could join. A classmate mentioned that some students were putting together teams for ‘‘case competitions,’’ contests in which participants proposed solutions to real-world business problems that were evaluated by judges, who awarded trophies and cash. The competitions were voluntary, but the work wasn’t all that different from what Rozovsky did with her study group: conducting lots of research and financial analyses, writing reports and giving presentations. The members of her case-competition team had a variety of professional experiences: Army officer, researcher at a think tank, director of a health-education nonprofit organization and consultant to a refugee program. Despite their disparate backgrounds, however, everyone clicked. They emailed one another dumb jokes and usually spent the first 10 minutes of each meeting chatting. When it came time to brainstorm, ‘‘we had lots of crazy ideas,’’ Rozovsky said.

One of her favorite competitions asked teams to come up with a new business to replace a student-run snack store on Yale’s campus. Rozovsky proposed a nap room and selling earplugs and eyeshades to make money. Someone else suggested filling the space with old video games. There were ideas about clothing swaps. Most of the proposals were impractical, but ‘‘we all felt like we could say anything to each other,’’ Rozovsky told me. ‘‘No one worried that the rest of the team was judging them.’’ Eventually, the team settled on a plan for a micro­gym with a handful of exercise classes and a few weight machines. They won the competition. (The micro­gym — with two stationary bicycles and three treadmills — still exists.)

Rozovsky’s study group dissolved in her second semester (it was up to the students whether they wanted to continue). Her case team, however, stuck together for the two years she was at Yale.It always struck Rozovsky as odd that her experiences with the two groups were dissimilar. Each was composed of people who were bright and outgoing. When she talked one on one with members of her study group, the exchanges were friendly and warm. It was only when they gathered as a team that things became fraught. By contrast, her case-competition team was always fun and easygoing. In some ways, the team’s members got along better as a group than as individual friends.‘‘I couldn’t figure out why things had turned out so different,’’ Rozovsky told me. ‘‘It didn’t seem like it had to happen that way.’’

The Work Issue: Reimagining the Office

1. How to Build a Perfect Team
2. The War on Meetings
3. The Case for Blind Hiring
4. Failure to Lunch
5. The 'Good Jobs' Gamble
6. Rethinking the Work-Life Equation
7. The Rise of White-Collar Automation
8. The Post-Cubicle Office
9. The New Dream Jobs

Yet many of today’s most valuable firms have come to realize that analyzing and improving individual workers ­— a practice known as ‘‘employee performance optimization’’ — isn’t enough. As commerce becomes increasingly global and complex the bulk of modern work is more and more team-based. One study, published in The Harvard Business Review last month, found that ‘‘the time spent by managers and employees in collaborative activities has ballooned by 50 percent or more’’ over the last two decades and that, at many companies, more than three-quarters of an employee’s day is spent communicating with colleagues.

Project Aristotle’s researchers began by reviewing a half-century of academic studies looking at how teams worked. Were the best teams made up of people with similar interests? Or did it matter more whether everyone was motivated by the same kinds of rewards? Based on those studies, the researchers scrutinized the composition of groups inside Google: How often did teammates socialize outside the office? Did they have the same hobbies? Were their educational backgrounds similar? Was it better for all teammates to be outgoing or for all of them to be shy? They drew diagrams showing which teams had overlapping memberships and which groups had exceeded their departments’ goals. They studied how long teams stuck together and if gender balance seemed to have an impact on a team’s success.

Which group would you rather join?

In 2008, a group of psychologists from Carnegie Mellon, M.I.T. and Union College began to try to answer a question very much like this one. ‘‘Over the past century, psychologists made considerable progress in defining and systematically measuring intelligence in individuals,’’ the researchers wrote in the journal Science in 2010. ‘‘We have used the statistical approach they developed for individual intelligence to systematically measure the intelligence of groups.’’ Put differently, the researchers wanted to know if there is a collective I. Q. that emerges within a team that is distinct from the smarts of any single member.

‘We had lots of data, but there was nothing showing that a mix of specific personality types or skills or backgrounds made any difference. The ‘‘who’’ part of the equation didn’t seem to matte