Project Aristotle, Psychological Safety, and High-Performing Teams
What Is Google’s Project Aristotle?
Project Aristotle was Google’s landmark study into team effectiveness, led by its People Operations division to identify what truly makes a high-performing team.
Across more than 180 teams and 250 variables, researchers discovered something unexpected: who was on the team mattered far less than how the team worked together.
The analysis revealed five consistent dynamics of effective teams:
Psychological safety
Dependability
Structure and clarity
Meaning of work
Impact of work
Among these, psychological safety emerged as the single strongest predictor of performance, innovation, and long-term success.
Why Psychological Safety Matters for Leadership and Performance
The foundation of psychological safety comes from Dr Amy Edmondson, Professor of Leadership and Management at Harvard Business School. Her research defined it as a shared belief that the team is safe for interpersonal risk-taking - meaning individuals feel free to speak up, question, or admit mistakes without fear of blame or humiliation.
When psychological safety is high, teams:
Share ideas more openly
Learn faster and recover from mistakes
Handle conflict constructively
Innovate more effectively
Achieve higher levels of trust and performance
Without it, people go quiet. Issues stay hidden, mistakes multiply, and performance drops, no matter how talented the individuals are.
Edmondson further broke down the concept into four stages, showing the different levels of trust within teams and organisations.
What Project Aristotle Revealed About High-Performing Teams
Google’s findings backed Edmondson’s theory with hard data. Successful teams consistently displayed certain patterns of interaction:
Equality in conversation – everyone had a voice.
Sensitivity to emotions – members recognised and responded to one another’s feelings.
Mutual dependability – people did what they said they would.
Clarity of purpose – everyone understood goals and roles.
Shared meaning and impact – work felt worthwhile.
These factors created what Google called team norms - the unwritten rules governing how people collaborate. Teams with strong norms of trust and openness outperformed those focused solely on technical skill or star talent.
The conclusion: psychological safety isn’t a soft extra; it’s a hard driver of performance.
The Five Dynamics of Effective Teams (Revisited)
Psychological Safety – Can people take risks and be honest without fear?
Dependability – Do team members reliably deliver?
Structure & Clarity – Are goals, roles, and plans clearly defined?
Meaning – Does the work matter personally to each person?
Impact – Do people see the tangible results of their contribution?
All five contribute to organisational performance, but psychological safety sits at the centre. Without it, the rest collapse.
How to Assess Psychological Safety in Your Team
Building high-performing leadership teams begins with understanding your current level of psychological safety. Start by:
Running an anonymous survey using Edmondson’s validated Psychological Safety Scale.
Observing behaviour in meetings: who speaks, who stays silent, how leaders respond to challenge.
Holding open conversations about trust, communication, and feedback.
Comparing perceptions between senior leaders and wider teams to identify blind spots.
Partnering with organisational specialists like Meraki People to conduct a structured team diagnostic.
Building a Culture of Psychological Safety
Psychological safety doesn’t appear by accident. It’s modelled and maintained through leadership behaviour.
To create it, leaders should:
Admit mistakes and model vulnerability.
Invite questions and challenge.
Respond with curiosity, not defensiveness.
Balance accountability with empathy.
Reinforce inclusive meeting habits so every voice is heard.
Teams thrive when leaders create clarity, consistency, and mutual trust. The reward is faster learning, better collaboration, and sustained high performance.
Conclusion: Psychological Safety as the Foundation of Performance
The evidence from Google’s Project Aristotle and Amy Edmondson’s research is conclusive: psychological safety is the cornerstone of effective leadership teams.
It drives creativity, resilience, and execution: the hallmarks of a culture built to scale.
At Meraki People, we help executive teams diagnose, develop, and embed psychological safety so their people and performance can flourish.
Explore our Team Diagnostic and Leadership Coaching Programmes to see how we can help you build a high-performing, psychologically safe culture where your best work can happen.