“Must be a team player.”

“Must be able to work collaboratively.”

How often have you seen requirements like these on job advertisements? Probably a lot in recent years. More and more companies are forming more and more teams to apply a range of skills and disciplines to tackle specific projects or initiatives. As this happens, the need for employees who can work successfully in teams is growing.

But what makes a good team player? And more to the point, what makes a good team?

It is not always clear why some teams work well together and produce great results where others can’t seem to get anything accomplished — even when the make-up of the teams are broadly similar.

Google, which operates thousands of teams through every part of its business, wanted to know the answer to that question and tasked its human resources staff (People Operations in Google-speak) to find the answer.

After intensive research over two years, Google found the answer — and it was not what they expected.

They thought that who was on the team was what made the difference — and they you could find that magic set of ingredients, it could be replicated and magic would be made.

Not so. As Judy Rozovsky, a member of the “Project Aristotle” team who conducted the research, wrote: “We were dead wrong. Who is on a team matters less than how the team members interact, structure their work, and view their contributions.”

What the research showed was that there was one key element to making a successful team. The key element is called psychological safety — teams where members felt they could take risks without feeling insecure or embarrassed were likely to be the most productive.

This was not entirely a secret. There has been quite a lot of academic research on the issue, but not all of it has been geared to teams. Psychological safety is important in all kinds of settings — a co-pilot who sees his plane captain turn the wrong switch has to fail safe to tell his superior he has made a mistake, and a nurse needs to be feel free to say when a dosage looks wrong on a patient’s medication. We all know the story of the Emperor’s clothes and how only a child had the nerve to point out the fact that the Emperor was naked.

But the principle is true for teams as well.

As Rozovsky states: “Taking a risk around your team members seems simple. But remember the last time you were working on a project. Did you feel like you could ask what the goal was without the risk of sounding like you’re the only one out of the loop? Or did you opt for continuing without clarifying anything, in order to avoid being perceived as someone who is unaware?

“Turns out, we’re all reluctant to engage in behaviours that could negatively influence how others perceive our competence, awareness, and positivity. Although this kind of self-protection is a natural strategy in the workplace, it is detrimental to effective teamwork.

“On the flip side, the safer team members feel with one another, the more likely they are to admit mistakes, to partner, and to take on new roles. And it affects pretty much every important dimension we look at for employees. Individuals on teams with higher psychological safety are less likely to leave Google, they’re more likely to harness the power of diverse ideas from their team-mates, they bring in more revenue, and they’re rated as effective twice as often by executives.”

To be sure, you have probably been on a committee where people are a little too free to speak, often over minutiae. Nothing much gets done in those circumstances either and that’s where the other four dynamics come in:

1. Dependability: can we count on each other to do high-quality work on time?

2. Structure and clarity: are goals, roles, and execution plans on our team clear?

3. Meaning of work: are we working on something that is personally important for each of us?

4. Impact of work: do we fundamentally believe that the work we’re doing matters?

So every team needs people who will deliver on what they are being asked to do, understand and agree on the goals and are motivated to do well.

That’s all well and good, and you can have all of these things in a team and still produce fairly average work. You need psychological safety to push the limits.

New York Times reporter Charles Duhigg reported that every member of teams with psychological safety spoke for the same amount of time and secondly, had “‘average social sensitivity’ — a fancy way of saying they were skilled at intuiting how others felt based on their tone of voice, their expressions and other non-verbal cues.”

The first point is vital — teams where one person dominates proceedings (sound familiar?) are less effective teams where all views are heard, roughly equally. This does not mean that everyone must be given five minutes each on every topic. People with deep knowledge in an area are likely to speak more on that area, but they should not dominate the areas where they do not. Conversely, people without deep technical knowledge should not be afraid to question assumptions or express their own point of view. Like the child and the Emperor, they might be the one to point out the problem that is standing in plain sight but no one else has seen it. What does matter is that over time, everyone has contributed equally.

Duhigg also points out that there is a difference between efficient teams and teams which practice psychological safety. Efficient teams tend to have clear leaders, and meetings may move forward with people speaking to their areas of expertise and moving on. It is efficient, and the work generally gets done, but it is not as productive as a team with psychological safety, even when the psychological team looks less efficient and more disorganised from the outside. “Efficient” teams where people are there to speak when they are spoken to are unlikely to produce many Eureka moments.

The important thing is that everyone should be committed and no one should be afraid to say what they think.

So if you are in a team, or leading a team, and feel that you’re not really going anywhere — or everyone else seems to be headed in the wrong direction, then ask yourself if your team is practising psychological safety! And if it isn’t, speak up!