A few years ago, a middle manager in a telecommunications company came to see me upon his promotion to a senior management role. I’ll call him Tobin Holmes (all case study names in this article have been disguised). A young Englishman who had studied classics at Oxford before graduating in the top 5% of his class at Insead, Holmes was very clever. But he feared he couldn’t take on the new job’s responsibilities.At the root of Holmes’s dilemma was his suspicion that he was just not good enough, and he lived in dread that he would be exposed at any moment.

A version of this article appeared in the September 2005 issue of Harvard Business Review.