Just a small amount of poison can make an entire lake toxic, and the same can be true when it comes to negativity in the workplace. You might have experienced this in your own office—one pessimist, one whiner, one complainer, or one troublemaker can infect the attitudes of an entire team or even department. And, because those behaviors are often perceived as inherent and unalterable personality traits, they go unchecked. But that’s an assumption that can have damaging results, including declining morale, decreased productivity, disengagement, and ultimately, turnover. It’s best to determine a solution to the behavior as soon as possible.

What can make this process difficult is that, often, problem employees don’t realize that they are causing issues in the office, and simply calling them out on the behavior might be met only with denial.

Here are some things to remember when you approach your problem employee:

• Try to understand rather than to immediately indict—discovering what’s motivating the behavior can lead to greater success in resolving it. When you talk with your employee, ask plenty of questions and be sure to be listen to the responses. Try to let the employee really get to the heart of what drives the behavior.

• When you talk to the employee about the issue, avoid getting into an argument. Use plenty of first-person feeling statements and avoid confrontational or accusatory language. If emotions do escalate in the conversation, maintain composure—losing your cool will only create more negative energy, won’t solve the problem, and could confirm for the employee that being pessimistic was correct.

• You might consider doing some role-playing, which will help the employee see things through your or another employee’s eyes and can help demonstrate the severity of the situation. It can also help illuminate a potential solution to the problem. Involving the employee in the steps to the outcome can engender greater buy-in and will help the employee feel empowered to shift his or her attitude.

• Once the problem is resolved (or at least when the employee begins to show effort toward change), think about ways to help ensure that negativity won’t crop up in the future, from that employee or from others. Communicate frequently with your group. The more transparent you can be about company plans, particularly around change, the less apprehension people will feel, which will help reduce nervous chatter and unfounded rumors.

• Set clear expectations (both for employees and for yourself), and follow through on what you say you’ll do. The more integrity you demonstrate, the harder it is for people to be negative about how things run. Don’t let trivial issues escalate. As soon as you recognize anything that has potential to become a real problem, nip it in the bud.

• Finally, surround yourself with the right talent. When you hire, do your due diligence—understand the needs of the role and employ best practices during the hiring process. Don’t rush to hire; take the time to interview properly, onboard effectively, and train thoroughly. That way, people can have greater productivity and job satisfaction out of the gate, and you’re less likely to have to deal with the toxic negative attitudes down the road.