Wouldn't it be great if every employee were an angel to work with? As managers and CEOs, it would make our jobs a heck of a lot easier, right?

Unfortunately, we've all had our own version of poison employees in our companies at one time or another. We try our best to weed out the suspicious ones during the hiring process, but how much do you really know about someone after a couple of interviews? And besides, bad behavior can take months, even years, to rear its ugly head.

The challenge is identifying poison employees and eradicating their behavior. Hopefully you can do this without eradicating them.

I've identified three types of employees that could be bringing your company down, but I'm sure there are others. Please add your own categories in the comments at the end!

Wendy the Whiner

Wendy is just waiting to find your company's mistakes (and we all have them), and will complain about them to anyone who will listen. Hopefully Wendy's peers will see through the whining, but it can really wear on anyone's nerves. Wendy will complain that the free soda you give out isn't all natural or the free pizza didn't arrive on time. She'll try to find flaws in you and surface them. She'll complain that her seat isn't ergonomic enough and her basic mission is to get people around her to be as miserable as she is.

Wendy's issue is not that your canned soda is not farm-to-table fresh; she's probably got issues outside of work. Is it your job to find out what those issues are? Not necessarily, but if Wendy is actually good at her job, you might want to address those issues and make them your own.

Sit Wendy down and gently let her know that it's been brought to your attention that she might not be happy at your company, and you'd like to know how you can make her day better. You might even ask her if everything is okay outside of the workplace. I did that once and my team member started to cry. Whiner turned weeper! But at the end, I had a clearer understanding of "why" it was happening and the employee realized that people around him were noticing. It worked out both ways.

Gary the Gossip

Gary is your most paranoid employee. He's constantly on the lookout for any information he can spread, either good or bad. "I heard we're getting sold." "Did you see who [insert your name here] was meeting with? I think they're getting let go!" "Did you see [insert name] was hanging out with [insert name] at the company party? I hear they're [insert scandalous thing here]."

You might not think you have a Gary at your company, but trust me, you do. What do you do with Gary? First of all, you need to keep close to the heartbeat of your company to even know what rumors Gary is spreading. If you are close to your people, engage with them and have gained their trust, someone will come to you and ask if what they've heard is true. Then you can address (if you can) your entire team and let them know that you've heard the gossip and put the kibosh on it (or not!) once and for all.

If the rumors start getting out of control, you might have to sit Gary down, tell him that if he "hears" any of this gossip to come to you instead of asking or telling his colleagues. You need him to stop the rumor mill, which will show him that you've entrusted him with this job without calling him out.

Recently at my company, VerticalResponse, we were meeting with a group of advertising executives who arrived dressed in suits. (We're a pretty casual company and jeans are the norm.) The rumors started that we were going to having an IPO. I told my team, "Trust me, if we're ever going to have an IPO, you'll all be very, very aware."

Harry the Hider

Harry is the best! He's the person who sets the bar low over in the corner and over-achieves every single time. You're continually surprised when Harry does anything good even if, in reality, it's so below the output compared to his peers.

Guess what? You're feeding Harry's underachievement.

The problem with Harry is not only is he an underachiever, but his peers see you letting that behavior go on and they might start thinking that's okay. They might ask, "Why does Harry get kudos for tying his shoe?"

How to deal with Harry? You need to start to measure Harry on smart goals and get him up to where he needs to be. What's a smart goal? Goals that are Specific, Measurable, Attainable, Relevant and Time-bound. This will clearly show Harry what he needs to do going forward.

Do you have poison employees? More importantly, how do you help them become a better team member? Chime in below!