I recently received an email from a former colleague who had changed jobs. “I haven’t worked this hard in years and have never felt so valued,” she wrote. “What a strange combination. I learn something new every day and am only worried my brain won’t hold any more information. I’m exhausted by Friday and it’s just great. Who knew?”

To me, by far the most important phrase in this uplifting note was “and have never felt so valued.” I guarantee that if this individual had just changed jobs, were working harder than ever and felt totally unappreciated, her experience of this new position and the tone of her comments would have been entirely different.

“I haven’t worked this hard in years and have never felt so unappreciated,” might have been the content of an alternate (fictional) communique. “What a combination! I have to learn something new every day and am worried my brain won’t hold any more information. I’m exhausted by Friday. Who knew things would turn out this way?”

Management implications: It’s widely accepted in the business world that an employee’s relationship with his or her direct manager is the single most important factor in employee engagement. If you dig deeper into employee engagement, there’s considerable excellent research that feelings of making continual daily progress are also key. And my own conclusion after years of in-the-trenches management is that nothing is more important than feeling valued.

It can be a difference maker, at times allowing employees to accept lower compensation, or longer hours, or the inevitable frustrations that accompany difficult tasks… than they otherwise might have… because they feel their efforts are recognized and appreciated. Time after time I’ve observed how small gestures of recognition and encouragement can change attitudes from disgruntled to pleased (or at least okay) in the blink of a manager’s eye.

The implications for management are clear.

This isn’t an invitation to abdicate managerial authority; naturally praise should never be given where it’s not deserved. But when it is deserved, there’s little for a manager to gain by being emotionally stingy.

If you value an employee, let him or her know it. If you don’t make that explicitly clear from time to time, they may well not realize it, even if you think they do.

Sincere words to that effect cost nothing and can make the difference between disengagement and productivity.

This article first appeared at Forbes.com.

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