Five years ago, several executives at McKinsey & Company, America's largest and most prestigious management-consulting firm, launched what they called the War for Talent. Thousands of questionnaires were sent to managers across the country. Eighteen companies were singled out for special attention, and the consultants spent up to three days at each firm, interviewing everyone from the C.E.O. down to the human-resources staff. McKinsey wanted to document how the top-performing companies in America differed from other firms in the way they handle matters like hiring and promotion. But, as the consultants sifted through the piles of reports and questionnaires and...
