Step one: ask employees if they would recommend you as a manager.

“Most managers have a remarkably narrow or ill-thought-out understanding of how their employees actually look at the world,” notes Julian Birkinshaw, a professor of strategy and entrepreneurship at London Business School and the author of Becoming a Better Boss: Why Good Management Is So Difficult (Jossey-Bass, 2013).

“Imagine what would happen if managers could get inside their employees’ minds and relate to their genuine motivations, needs and fears,” he continues. “My guess is that those managers would start doing a dramatically better job. Not only would they know how to motivate each individual employee, but they would also become less self-centered.”

His advice? Find out the answers to a single question: Would your employees recommend you?

A condensed question, which strips away the language and diluted focus of so many assessments, is a better and more focused way of getting at the true quality of a manager, he argues. Birkinshaw made his observations in “Would Your Employees Recommend You?”, in the Fall 2013 issue of MIT Sloan Management Review.

The idea derives, Birkinshaw says, from the work of Frederick F. Reichheld, founder of Bain & Company’s loyalty practice and author of the seminal 1996 marketing book The Loyalty Effect. Reichheld developed a customer-relationship metric called Net Promoter Score designed to measure customer passion for a company.

In a 2006 article for MIT SMR, Reichheld described the idea around NPS this way: “A company asks its customers just one question — ‘How likely is it that you would recommend us to a friend or colleague?’ — and then scores the results on a zero-to-10 scale with 10 representing ‘extremely likely’ and zero representing ‘not at all likely.’” Reichheld adds that “customers who give the company a nine or 10 rating … are known as ‘promoters’ because they behave almost as if they were adjuncts to the organization’s sales force.” A company’s NPS is the percentage of promoters minus the percentage of detractors — those who give a company ratings from zero to six — and is a metric that, Reichheld writes, “turns out to correlate well with increases in a company’s growth rate.”

That same concept, Birkinshaw maintains, applies just as well inside a company. “Your employees aren’t just passive recipients of your efforts to create a great place to work; they are also potentially your biggest promoters,” he writes. Highly engaged employees “make a real difference, because their enthusiasm is infectious.”

The NPS metric as Reichheld developed it is used to measure how external stakeholders — customers — feel about an organization, but Birkenshaw used it internally at Hoffmann-La Roche Ltd., the Swiss pharmaceutical company. There, the team adapted Reichheld’s phrasing to ask, “How likely is it that you would recommend your line manager to a colleague, as someone they should work for in the future?” The company found that results where employees scored their managers highly were strongly correlated to Roche’s broader measures of employee engagement.

This measurement serves two purposes, Birkenshaw says. “First, it is a useful overall indicator of the workplace climate in a unit or organization.” Second, it can be used as feedback for individual managers.

One caution: direct feedback is not for the faint-hearted. “There is nowhere for the manager to hide if his or her score is negative,” Birkenshaw notes. “But increasingly companies are recognizing that this type of feedback is necessary for improvement to take place.”

Bottom line, Birkenshaw says: “Employee engagement is an indicator of how much discretionary effort a person is likely to put into his or her job, and it is influenced by a range of factors, including the nature of the work, the physical working environment, the development opportunities and the quality of colleagues.” The high correlation between employee engagement and the ‘would you recommend your boss’ question suggests, he writes, “that all these other factors may be secondary. No matter how good a workplace a company provides, it may all come to nothing if the employee dislikes his or her immediate line manager.”

For more details, read Birkshaw’s full article and Reichheld’s “The Microeconomics of Customer Relationships” in the MIT SMR archives.