What is The Extraordinary Leader about?

The Extraordinary Leader is one of the more research-grounded leadership books of its era. Zenger and Folkman built their argument on a dataset of 360-degree feedback assessments covering more than 20,000 leaders, and their core finding is genuinely counterintuitive: fixing weaknesses makes a mediocre leader adequate, but it doesn't make an adequate leader great. What separates extraordinary leaders from good ones is the development of a small number of profound strengths — not the elimination of all deficiencies.

The book identifies sixteen competencies grouped into five clusters: character, personal capability, focusing on results, interpersonal skills, and leading organizational change. Extraordinary leaders don't excel at all sixteen. What they do consistently is score in the top quartile on a handful of competencies that are central to their role, while having no "fatal flaws" — severe weaknesses that actively undermine their effectiveness.

A key insight is what the authors call "cross-training": developing a strength in one competency by pairing it with a strength in a related competency. Leadership behaviors tend to reinforce each other, and the combination of two strong behaviors is often more powerful than either alone. This has practical implications for development planning — rather than spreading development across all sixteen, a leader should identify their top strengths and deepen them.

The book's data-driven approach is a genuine differentiator. The arguments aren't based on interviews with admirable leaders or on theoretical frameworks — they're based on observable patterns across tens of thousands of assessments. The weakness is that the data comes from the authors' own consulting practice, which limits independent verification. But the core thesis — develop strengths, fix fatal flaws, don't waste development time on middling weaknesses — holds up against other research traditions and is more actionable than most leadership models.