How to Make Your Team Feel Safe Bringing You ProblemsAdvertising an 'open door' isn't enough.Team members need to truly believe that you'll hear them out and take action.

Plenty of leaders say they offer an "open door policy" to encourage employees to bring them problems or concerns. Many of these leaders also ask that employees voicing concerns come prepared with solutions in order to take responsibility for the problem rather than just "dump" or "vent."

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But employees in those scenarios may get the idea that it's unacceptable to raise problems in the business if they don't know how to fix them. In fact, in a study of a phenomenon they dubbed "employee silence," professors from New York University's Stern School of Business demonstrated that 85 percent of their respondents felt they couldn't raise important issues to their management at all.

Is this happening at your company? If you're not regularly hearing about your team members' challenges and frustrations, you can't conclude that all is well: In fact, you might be missing out on vital information that could help you make crucial decisions about your business. You might also end up losing employees who would otherwise be able to make significant contributions.

The good news is that there are ways to reduce these risks. Try the following techniques to encourage employees to speak their minds and feel confident that you'll take their comments into account.

Tell them why you need to hear from them as a matter of business.

Emphasize that your openness isn't because you're nice or merely want to placate them. Instead, explain that you recognize the downside of not understanding employees' opinions or acknowledging the risks of having a disengaged workforce, i.e., high turnover.

Research backs up this concern:AHarvard Business Reviewstudy by James R. Detert and Ethan R. Burrisfound that, "When employees can voice their concerns freely, organizations see increased retention and stronger performance."

Teach employees to use code words.

These will signal to you when they're coming in with an important matter and want you to hear them out. For example, many of my clients now tell one other to "put their seatbelts on" to signal that they need to have a tough conversation and want to cue the other party that it's important to keep cool and maintain an open mind on the issue.

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Research from Fierce Conversations and Quantum Workplacefound that although about half of employees studied didn't speak up regularly, the employees who always or almost always "speak their minds reported being more engaged at work than those who said they never or almost never did so."

A mutually agreed-on process for ensuring attentiveness goes a long way toward helping employees speak up.

Go and seek them out.

If you haven't heard from crucial individuals for a while, or you suspect there's an issue brewing no one has talked to you about, create the forum for a discussion yourself.

This doesn't have to mean summoning people to your office. One of the CEOs I work with says, "I don't know what I don't know," and periodically walks the floor, chatting with everyone and lingering longer and probing more deeply with influencers and opinion leaders to learn what's really going on.

Show that you act on their input.

Refer to times when you took someone's opinion and were able to improve a situation. Be explicit, so that the participants and other employees can tell you mean it. You could say something like, "Once Sally told me what was going on, it got me thinking. So I reevaluated that supplier's performance, and asked them to improve their level of service. Now we've got a better deal."

Use a meeting and report structure.

One of my clients was slow about taking action on employee concerns. As a result, her employees stopped informing her of problems altogether, and instead ratcheted up the conflict among themselves.

This outcome matched the findings of theJournal of Business Ethicsstudy,When Employees Stop Talking and Start Fighting,whose authors wrote that, "Negative consequences are particularly likely to occur when employees perceive the opportunity to voice opinions to be … given by managers who do not have the intention to actually consider employee input."

To correct the problem, this leader started holding weekly meetings to ask employees what was new or bothersome and to make public lists of the issues that needed attention.

Create an advisory group or process.

Another of my clients knew he wasn't hearing enough candid feedback from his team. He created an advisory council that collected concerns from the entire group and met with the leader quarterly to share them. This felt less risky personally to the individual employees and helped create a consistent feedback loop.

Related:7 Signs Your Employees Are Unhappy and What to Do About It

Overall, employees may always have some nervousness about raising tough topics to their leaders. But if you take the time and trouble to make clear that you care about their feedback and intend to take it seriously, they'll be much more likely to share their concerns and deepen their commitment to you and the company.