If one of your highest performing employees is also one of your most toxic, what should you do? As productive as they might seem, these so-called toxic rock stars are a major problem and can drive away your other valued employees. Here’s what to do if you have a toxic employee on your team.

Take an honest look at your culture. If you suspect the person is not an outlier, or the only one participating in toxic behaviors, conduct a culture survey, focus groups, and one-on-one conversations with your employees to learn more. It’s important to know how you might be contributing to the problem, or allowing it to persist. Don’t be defensive about what you find — respond with humility, curiosity, and empathy.

Establish a reliable feedback process. Provide anonymous reporting opportunities so employees can feel confident they won’t be penalized for speaking up about a toxic colleague — especially if that person has a lot of organizational power and influence.

Establish a no-tolerance policy. Decisive action is critical. Otherwise you risk sending the message that bad behavior is OK as long as people are delivering results.

This tip is adapted from “Leaders, Stop Rewarding Toxic Rock Stars,” by Deepa Purushothaman and Lisen Stromberg