In today's rapidly changing and complex world, it is increasingly important to have a diversity of perspectives and ideas to tackle the most challenging problems. However, simply having a diverse team is not enough; the team must also have psychological safety—the ability to share their ideas without fear of criticism or negative consequences.

The consequences of lack of diverse thinking or psychological safety

The Failure to Anticipate 9/11: Lack of diversity

There’s strong evidence to suggest that the failure to anticipate 9/11 was the ‘collective blindness’ of the American CIA; this is attributed to its complete lack of relevant diversity. Almost all the CIA agents were white, American, well-educated males with a generally conformist and obedient culture. There were no Muslims.

The key messages delivered by Bin Laden were not given the attention they deserved because the Agency perspective had insufficient diversity and lacked staff who would see those messages for what they were. For example, most agents gave no credibility to a man in threadbare clothing standing in front of a cave threatening America; whereas those of the Islamic faith would recognize the spiritual association with Mohammed, who lived in a cave and dressed in a similar fashion.

The Mt. Everest Disaster of 1996: Diverse perspectives are insufficient

Eight lives were lost on Mt. Everest on a stormy night in 1996. The expedition leader, Rob Hall, was vastly experienced and respected, with several successful visits to the summit already behind him. As the ensuing storm developed and worsened, though, several members of the team could see difficulties that the leader was unaware of—yet they failed to offer their diverse but valuable perspectives.

Diverse thought leadership and the success of Silicon Valley

In contrast, Silicon Valley’s triumphant success as the hub for successful entrepreneurial IT was built not exclusively on attracting high talent, but also in having an environment that encouraged diverse views to be shared. A local café, the Wagon Wheel, in effect became a brainstorming and problem-solving hub where the sharing of ideas and solutions from among a diversity of backgrounds and insights was a major contribution to everyone’s success.

Psychological safety is equally essential

Diversity of thought can be a major help or hindrance to solving problems, particularly in a VUCA environment (one which is Volatile, Uncertain, Complex and Ambiguous). Much has been said, particularly recently, of the need to share different perspectives, often in group settings. This is particularly the theme of Matthew Syed’s excellent book, Rebel Ideas: “Solutions to complex problems typically rely on multiple layers of insight and therefore require multiple points of view.”

However, diversity of thought alone is not enough. It is not the only factor leading to success or failure in the examples above. For diversity of thought to work, a second ingredient must be present: psychological safety.

As defined by Amy Edmondson, psychological safety is a condition where, within any collective, the sharing of ideas is valued and encouraged and everyone feels safe from damaging criticism or ridicule, even or especially if the ideas are rejected.

Edmondson says: “Psychological safety is a shared belief, borne out in fact, that everyone in the team is safe for personal risk taking.”

Psychological safety and organizational culture

Even if the CIA had had a cultural mix of staff able to interpret events leading to 9/11 in a different and helpful way, would they have felt sufficiently empowered to voice their view?

On the summit of Mt. Everest, there were enough different eyes and ears to perhaps have offered information that, when combined, would have enabled the team to better manage the imminent danger. However, on the final push to the summit, expedition leader Rob Hall had told the team that under no circumstances should his decisions be challenged since he was responsible for what happened on the ascent. This resulted in “group-thinking”; because there wasn’t a first person willing to break that collective thinking, nobody in the group ended up speaking. A lack of psychological safety prevented the group members from acting—with devastating results.

Steps you can take for a more inclusive, ‘safe’ leadership

Leaders in businesses large and small can take an equality, diversity, and inclusion training course as a valuable step toward becoming a more knowledgeable and well-rounded individual in today's diverse and ever-changing society. By incorporating equality, diversity, and inclusivity into their professional development, team members can gain a deeper understanding of unconscious biases and how they can impact workplace dynamics, as well as learn strategies to promote inclusivity and create a more welcoming environment for all employees. This can lead to improved employee satisfaction and retention, better problem-solving and decision-making, and ultimately, increased productivity and profitability for the business.

Teams can also use a reflective practice to ensure that they are consistently implementing the principles of equality, diversity, and inclusion in their daily operations. This can involve regularly examining their own biases, seeking feedback from colleagues from diverse backgrounds, and actively seeking out opportunities to promote and support diversity in the workplace.

By combining formal education with ongoing reflection and action, teams can create a more inclusive and supportive environment that values the unique perspectives and experiences of all individuals. An environment where speaking up is safe.


Though both concepts—diversity of thought and psychological safety—are separately known and promoted, neither can succeed without the other. They are inevitably connected: No team is going to share diverse thoughts if they are likely to face unwanted repercussions. And psychological safety is at its most powerful and helpful when there is a need for and presence of diverse perspectives.

In Silicon Valley, where the highly intelligent IT whiz kids felt safe enough to share and learn, innovation flourished. As Joe Henrich, a key researcher of Silicon Valley, puts it: “To have cool technology, it is better to be social than smart.”

Which might, for the purposes of this article, be amended to: “To be successful in VUCA environments, it is better to be social and safe than smart.”