The 4 Stages of Psychological Safety: Defining the Path to Inclusion and Innovation
A practitioner book by Timothy R. Clark, published by Berrett-Koehler in 2020, which sets out a model of four successive stages of psychological safety. The publisher describes it as a 'practical, hands-on guide' for leaders, offering what it calls a 'research-based framework': leaders who cultivate psychological safety move teams and organisations through four stages, from feeling included and accepted to feeling safe to learn, then to contribute and, finally, to challenge the status quo. The stages are inclusion safety (also called member safety), learner safety, contributor safety and challenger safety. The synopsis is addressed to leaders: 'perhaps the leader's most challenging task is to increase intellectual friction while decreasing social friction', and Clark shows how 'leaders can, and must, set the tone and model the ideal behaviors'.
LeaderFactor, Clark's company, now describes psychological safety as 'a culture of rewarded vulnerability' built on two drivers, respect and permission. As both increase, a team climbs the four stages in sequence, and each stage runs on a social exchange: 'inclusion in exchange for being human and harmless', 'encouragement in exchange for engagement', 'autonomy in exchange for results' and 'air cover in exchange for candor'. The first edition has contributor safety offered 'in exchange for effort and results'. The framework is trademarked and taught through LeaderFactor's own course, with its PSindex assessment and certification for in-house facilitators. LeaderFactor lists Spanish, Portuguese, German, Mandarin and Japanese editions.
A second edition, subtitled How to Build a High-Performance Culture, followed in August 2026. Its publisher says it adds quantitative evidence from Clark's global database of 1.2 million data points, 'validating the four-stage model across cultures and demographics', with new chapters on what psychological safety is not, the dangers of 'nice' cultures, psychological and physical safety, and measurement. LeaderFactor says the core framework is unchanged. We have not seen the data behind the validation claim.
We have written about the model twice (Tom Geraghty), and the second piece calls the first somewhat generous. In our reading the stages are not really stages but different aspects of psychological safety, which vary independently; there is no body of peer-reviewed research showing teams moving through them in sequence; the book arguably overemphasises the leader's responsibility, where we find it needs to be shared by the whole team; and respect and permission are conferred by those with more power, so that permission to challenge is granted by the person being challenged. An organisation that adopts the model and concludes the work is done can leave the people it serves least well less safe, not more. We see its use as a vocabulary, for noticing that psychological safety is not binary and that feeling safe to offer an idea is not the same as feeling safe to dissent, to be used with great caution and held lightly. Built from the publisher's descriptions of both editions, catalogue records and LeaderFactor's published account of the framework, alongside our two critiques; the book's text was not read for this entry, though Tom confirmed the stage names and checked the first edition's wording on contributor safety.
Save this paper to a bibliography, keep notes on it, and export citations. Create a free account →
Neighbours (12)
- Psychological Safety and Learning Behavior in Work Teams
- The Fearless Organization: Creating Psychological Safety in the Workplace for Learning, Innovation, and Growth
- A Leader's Framework for Decision Making
- The Giving of Orders
- Time and Transition in Work Teams: Toward a New Model of Group Development
- Building a Fearless Organization: A Fieldbook for Creating Psychological Safety at Work
- Four Stages: a Six-Stage Critique
- Reducing Power Gradients
- All Models are Wrong
- Four Stages Critique
- Power & Mary Parker Follett
- Tuckman's Model