Rolling your eyes in a meeting; talking about a colleague behind his back; dragging your feet with a project you don't agree with. This brand of passive-aggressive behavior isn't just unhelpful, it's downright destructive for your business.

When someone is being passive-aggressive, she is expressing hostility--albeit indirectly. This behavior is an attempt to avoid conflict, but it creates a special brand of conflict that can hurt the entire team, says Liane Davey, the author of You First: Inspire Your Team to Grow Up, Get Along, and Get Stuff Done.

"The cost of passive-aggressiveness is high," Davey writes in a recent article for Harvard Business Review. "At the business level, the negative effects include slow decision making, poor risk identification and mitigation, and stalled execution."

It's a problem when your managers or employees don't speak up when they disagree with the direction of a project or avoid talking things out with a colleague they have a problem with, says Davey. She adds that the "unarticulated frustrations" can "erode trust," damage communication and create animosity. When that happens, "everyone suffers," she says.

Avoiding direct conflict is a huge waste of time. As a leader, you should instead look to encourage it. Here are four ways to support clear lines of communication and root out those passive-aggressive tendencies. 

1. Establish the need for direct conflict.

The first thing you need to do is to tell your employees about the "need for conflict," Davey says. Your company needs to stop being passive-aggressive and instead be open and direct with opinions, problems, or issues, she adds. Explain how to bring valuable debates and discussions in front of the team before decisions are made. If people come to your office after a meeting to bring up their issues, explain that the meetings are the proper venue for their opinions. 

2. Make room for dissent.

The next time you're in a meeting and making decisions, ask if anyone has criticism on the idea or project. Ask questions like this: How could we improve this project? What are the main counterpoints to this decision? Who has an idea we haven't discussed?

"You want people to feel like they are contributing positively by raising a conflicting perspective," Davey writes.

When employees do bring up a different idea, address it and reward them for being direct. Ask the team what they could learn about this different point of view. If an idea is good but many people disagree with it, Davey says, you should softly support it by asking for their reasoning. Get them to explain their thought process.

3. Publicly address passive-aggressive behavior.

If you want passive-aggressive behavior to stop, you need to make it uncomfortable for people who display the unwanted behavior. "Make sure you identify passive-aggressive behavior every time you see it," she says. "For example, when body language is negative, ask, 'I've noticed that you've pushed away from the table. How are you reacting to this discussion?' or 'I just saw three people roll their eyes. What's going on?'"

If someone makes a sarcastic remark, don't let the comedic relief distract you, says Davey. Make sure to dig in and get to the bottom of the remark.

4. Close all back channels.

"Finally, you need to shut down all back channels. Those meetings after the meeting need to stop," Davey says. When the typical crew of employees come to complain to you after meetings, you need to address it and say how you're concerned about why they didn't speak up during the meeting. "What are you hoping to accomplish by raising it now," Davey suggests asking. Tell them how this behavior is not acceptable and explain how their opinions are important, but they have to be direct.