You won’t find it on a resume, but it’s one of the most important factors a worker brings to the job: personality.

Some personality types are so toxic they can poison everyone around them.

The so-called “Eeyore”—the donkey of Winnie the Pooh fame who suffered from persistent negativity—can leave even upbeat co-workers feeling down. The “Blamers” never take personal responsibility, even when they should. “Credit Thieves” demoralize co-workers. “Drama Kings” and “Drama Queens” suck oxygen from the workplace.

“We’re really good at dealing with skills stuff,” in hiring and performance reviews, said Mark Murphy, founder of D.C.-based Leadership IQ, a leadership training and research firm. “Eighty-nine percent of hiring failures come from attitude rather than skills issues.”

But experts said there are ways human resources managers can handle problem personalities.

The Eeyores

Like the character in the children’s books, these folks always see the cloudy side. Their attitude is: the project can’t possibly be done; the company will never succeed; they are never treated fairly.

Too often, managers feel they have to change themselves or the work environment to suit this negative person. “They end up damaging the [other] 90 percent of people” who have a positive outlook, pointed out Dean Debnam, CEO of Workplace Options, a Raleigh, N.C.-based work/life benefits company.

If the workplace Eeyore is allowed to get away with doing less because of his or her complaints, team productivity can drop as other employees begin to ask themselves, “Why am I working this hard?”

HR managers should use objective performance measures to show an Eeyore that people can and do meet job demands that the Eeyore claims are unreasonable.

The Blamers

These types of workers blame their failures on other people and departments, Murphy said. “Even a little bit of blame can become infectious,” he said.

In such a climate, other workers can become defensive and a bit paranoid, worried that the Blamer may throw them under the bus, Murphy said. Thus, he said, they can waste “10 percent to 15 percent of their time on activities that are nothing more than covering themselves.”

HR’s role in this case is to coach managers to foster a culture where problems are addressed before they fester, and where employees can feel safe admitting mistakes and learning from them. It’s important not to blow errors out of proportion or to come down too hard on workers because of infractions. “You can’t have a ‘gotcha’ culture,” Debnam said.

The Credit Thieves

When leaders aren’t paying close attention to who’s really contributing, Murphy said, employees can get away with stealing the credit for others’ work. This can happen especially in companies where people work in teams, but are rewarded individually.

The Credit Thieves often get away with this behavior because they are favorites of managers in top-down hierarchies. Peer reviews like 360-degree assessments can bring the problem to light.

Drama Royalty

Drama Kings and Queens react emotionally to almost everything—whether it’s a work setback or personal crisis—and try to lure colleagues into their theatrics. “They’re toxic because no one can get anything done when they’re all stirred up emotionally,” Murphy said.

HR managers should first focus on the facts behind what’s upsetting the employee, leaving emotional elements out of the conversation. Next, they should invite the worker to focus on key aspects of the problem at hand to encourage them to take personal responsibility and address the issue head-on.

The Volcanoes

Volcanoes are prone to sudden outbursts punctuated with dramatics, such as screaming or throwing things. They often end up in leadership jobs because they are bright extroverts and appear perfect on paper.

However, these types of employees tend to unravel under stress, said Scott Davies, who has a Ph.D in industrial and organizational psychology and is the head of PointLeader Inc., a Northern Virginia talent management system that uses personality- and ability-based predictive assessments. While their bosses often don’t see the problem, their subordinates live in fear of the next blowup. Often, the Volcano’s tenure is marked by the resignations of people who had to work under this turbulent management style.

Executive coaching can help Volcanoes figure out their stress triggers and learn how to react more appropriately, Davies said.

Whatever the difficult personality, try to avoid hiring them in the first place by using personality and attitude assessments during the hiring process, Murphy advised.

If the problem person is already on board, HR managers need to encourage managers to put personality problems into performance reviews—noting specific behaviors that have caused problems, Murphy said.

Tamara Lytle is a freelance writer based in Washington, D.C.