In 1998, Daniel Goleman published a paper in Harvard Business Review that changed how organisations think about leadership selection. Its conclusion — that emotional intelligence is the critical differentiator between average and exceptional leaders — was provocative at the time and has since been validated by a substantial body of research. Yet most organisations still hire and promote leaders primarily on the basis of technical expertise, intellectual credentials, and track record in prior roles. The EQ data remains largely ignored in practice. This article examines what the research actually shows — and what it means for how you develop and assess leaders.
Goleman's five components: a precise framework
Goleman's model of emotional intelligence is frequently misunderstood as a vague concept about being "nice" or "emotionally sensitive." It is neither. The model identifies five specific, measurable capabilities, each with distinct behavioural expressions and each with documented links to leadership outcomes.
These five components are not personality types — they are capabilities, and like all capabilities, they exist on a spectrum. Critically, unlike IQ, they are developable. A leader can meaningfully improve their self-awareness through structured feedback and coaching. A leader can build self-regulation skills through deliberate practice. This is one of the most important distinctions between EQ and IQ — and it has profound implications for how organisations approach leadership development.
The 90% finding — and what it actually means
TalentSmart, a research and consulting firm that has assessed over a million people across industries, found that 90% of top performers score high on emotional intelligence — and that EQ accounts for 58% of the variance in job performance across all types of jobs. The findings are most pronounced in roles with high interpersonal complexity — which is to say, in leadership roles at virtually every level.
of top performers score high on emotional intelligence. EQ accounts for 58% of performance variation across all job types. Source: TalentSmart, 2023.
It is worth being precise about what this means and what it does not. The 90% finding does not mean that every emotionally intelligent person is a top performer. IQ, domain expertise, and opportunity all matter. What it means is that among people who are performing at the highest level, EQ is almost universally present — suggesting it is a necessary, if not sufficient, condition for sustained excellence in leadership roles.
The IQ ceiling: where EQ becomes the differentiator
The relationship between IQ, EQ, and leadership effectiveness is not simply "EQ matters more than IQ." It is more precisely this: above a cognitive threshold — estimated by Goleman at around IQ 120 — additional increments of IQ produce diminishing returns in leadership effectiveness, while EQ continues to predict performance strongly. Below that threshold, cognitive ability is the gating factor. At and above it, it is emotional intelligence.
This has a specific and practical implication for senior leadership selection. The population from which organisations select Vice Presidents, Directors, and C-suite leaders is almost uniformly above the cognitive threshold for those roles. In this population, intelligence is a constant, not a variable. Differentiating on IQ at this level is the wrong analysis. The question is not "how smart is this person?" — they are all smart enough. The question is "how emotionally intelligent are they?" And that question requires a different kind of assessment.
Bar-On's research: EQ and organisational outcomes
Reuven Bar-On, one of the founders of modern EQ research, developed the Bar-On Emotional Quotient Inventory (EQ-i) — one of the most widely used and validated EQ assessment tools globally. His research across diverse organisational settings established robust links between specific EQ dimensions and concrete organisational outcomes: customer satisfaction, revenue generation, safety incident rates, absenteeism, and employee retention.
Bar-On's work is particularly valuable in identifying the EQ profiles associated with different leadership challenges. Leaders facing change management demands show a distinctive EQ signature: high adaptability, high stress tolerance, and high optimism. Leaders in high-stakes crisis situations show high impulse control and high reality-testing. These are not vague descriptions — they are specific, measurable EQ capabilities that can be assessed before a leader is placed in a role, not diagnosed after they struggle.
The neuroscience: why amygdala hijack matters
The neural architecture of emotional intelligence is now well understood. The amygdala — the brain's threat-detection centre — responds to perceived social and emotional threats with the same physiological response it generates in response to physical danger: cortisol and adrenaline flood the system, the prefrontal cortex (responsible for rational decision-making and self-regulation) is effectively taken offline, and behaviour becomes reactive rather than considered.
This is what neuroscientist Joseph LeDoux called the "amygdala hijack," popularised in leadership contexts by Goleman. In team settings, the implications are significant. A leader who experiences frequent amygdala hijacks — who becomes reactive under pressure, who responds to challenge with defensiveness or aggression — creates a cascade of threat responses in their team. Team members enter a state of heightened vigilance. Psychological safety collapses. Candour disappears. The team reverts to telling the leader what they want to hear rather than what they need to hear.
"In leadership, emotional intelligence matters almost twice as much as IQ and technical skills for jobs at all levels." — Daniel Goleman, Working with Emotional Intelligence, 1998
High-EQ leaders manage this neurobiology. Through self-awareness and self-regulation, they recognise the early signals of emotional activation and apply the cognitive tools to prevent escalation. In doing so, they protect the psychological safety of their teams — which Google's Project Aristotle identified as the single most important factor in team effectiveness. This is not soft science. It is a direct causal chain from leader EQ to team psychological safety to team performance.
EQ in team dynamics: the compounding effect
EQ is not just an individual capability — it has powerful collective effects in teams. Research on group emotional intelligence, advanced by Vanessa Urch Druskat and Steven Wolff in a 2001 Harvard Business Review study, found that teams with high collective EQ outperformed low-EQ teams significantly on measures of coordination, adaptability, and output quality. The mechanism is psychological safety: high-EQ teams create environments in which members feel safe raising concerns, admitting mistakes, and challenging assumptions — the conditions that enable both high performance and rapid learning.
Teams with low collective EQ, by contrast, are characterised by unspoken tensions, defensive attribution (blaming others or circumstances for failures), and a pattern of surface agreement that conceals fundamental disagreement. These are the teams that seem functional in calm conditions and fall apart when faced with a genuine crisis.
The most important fact: EQ is developable
Unlike IQ, which is largely stable across adulthood, EQ is meaningfully developable — particularly with structured feedback, coaching, and deliberate practice. This is perhaps the most important implication of the EQ research for organisations. It means that investing in EQ development is not a gesture towards personal growth — it is a productivity investment with documented returns.
The development of EQ in leaders requires specific conditions: honest, structured feedback on the impact of current behaviours (which 360-degree assessment provides); a coaching relationship that creates the psychological safety for genuine reflection (which leadership coaching provides); and sustained practice with real-world application. These conditions cannot be replicated in a two-day workshop. They require a designed, sustained development process.
Assessment is the starting point. Leaders who understand their current EQ profile — their specific strengths, their characteristic blind spots, and the situations that trigger their least effective responses — can target development with precision. EQ assessment through TeamAnalys provides this baseline, giving coaches and HR leaders the data they need to design development that actually changes behaviour rather than simply informing leaders about the concept of emotional intelligence.
Assess EQ. Develop it. See the difference.
TeamAnalys offers validated EQ assessment tools and coaching programmes designed to develop the emotional intelligence of your leaders and teams.
EQ assessments → Leadership coaching Talk to usReferences: Goleman, D. (1998). What Makes a Leader? Harvard Business Review, 76(6), 93–102. Goleman, D. (1998). Working with Emotional Intelligence. Bantam Books. Bar-On, R. (2006). The Bar-On Model of Emotional-Social Intelligence. Psicothema, 18, 13–25. TalentSmart (2023). EQ Applied: The Real-World Guide to Emotional Intelligence. Druskat, V.U. & Wolff, S.B. (2001). Building the Emotional Intelligence of Groups. Harvard Business Review, 79(3), 80–90. LeDoux, J. (1996). The Emotional Brain. Simon & Schuster. Google re:Work (2016). Project Aristotle: Understanding Team Effectiveness.