In 2012, Google launched one of the most ambitious team-performance studies in corporate history. Called Project Aristotle, the research examined 180 teams across the organisation with a simple goal: find out why some teams consistently outperform others.
What They Expected to Find
The early bet was simple: the best teams would be packed with the best individuals — the highest performers, the smartest people, the most experienced professionals. Assemble stars; get star results.
The data quickly dismantled that assumption.
What They Actually Found
After analysing hundreds of variables — team composition, seniority, skills mix, communication patterns, meeting structures — one factor stood out as the strongest predictor of team success: psychological safety.
Psychological safety is the shared belief that people can speak up, take risks, admit mistakes, and ask questions without fear of embarrassment or punishment. Teams with high psychological safety outperformed peers on innovation, execution speed, quality, and member wellbeing.
Five Characteristics of High-Performing Teams
Project Aristotle identified five key dynamics, in order of importance:
- Psychological safety — Can we take risks without fear?
- Dependability — Do we deliver on what we commit to?
- Structure and clarity — Do we know our goals, roles, and plans?
- Meaning — Is our work personally meaningful?
- Impact — Do we believe our work matters?
Notably absent: skills, IQ, and experience — as well as compensation, titles, or team size.
The Role of Emotional Intelligence in Team Performance
Policies don’t create psychological safety. Behaviour does — especially the behaviour of leaders. Leaders who model vulnerability, admit errors, invite dissent, and respond with curiosity rather than defensiveness foster safety. Those who manage through control and criticism erode it quickly.
Applying This to Team Building
If you want a high-performing team, don’t start with a skills audit. Begin by understanding the emotional dynamics in the room. Who sets the tone? Where is there unspoken tension? Who adapts under pressure, and who withdraws?
Answering these questions calls for different tools than a CV: behavioural profiles, emotional intelligence assessments, and honest coaching conversations.
The Practical Takeaway
High-performing teams are built deliberately by leaders who understand the human dynamics beneath the surface and create conditions where those dynamics help rather than hinder. That is the science. The art is putting it into practice.