How to handle toxic coworkersThey slow you down, irritate you and sometimes they're just plain useless. You know who they are -- those toxic team members who never seem to actually contribute anything to projects or to your work environment but who have an uncanny ability to stay employed and come out of every situation smelling like the proverbial rose. \n"While 75 percent of employers rate team work and collaboration as "very important," most employees hate working together in teams because there's inevitably at least one person who make the experience horrible. It may not be deliberate; it may be that these folks are brilliant but just lack social skills. Whatever the case, it's detrimental to the rest of the team and the company," according to Alexander Maasik, communications specialist with workplace productivity solutions company Weekdone. Here, Maasik offers the five most common enemies of teamwork, and the best way to handle them as a leader or as a co-worker.\n1. False promises Image by ThinkstockEspecially in high-pressure situations, it's so tempting to over-promise in the hopes of gaining recognition or pleasing your supervisor or company leadership. It's easy to make the promise -- "Sure, we can deliver that project in six weeks" -- but you have to make certain you can deliver, Maasik says. \n"If there's a team member or co-worker who's constantly making empty promises you know they can't keep is to take everything they claim with a grain of salt. If you can, add time, budget or resources to projects to compensate for the areas you know are going to come up short," Maasik says.\n[ Related story: Stop workers from quitting in their seats ]\n2. Along for the rideImage by ThinkstockThen, there are people who interpret the shared responsibility of teamwork as "everyone else is responsible," Maasik says. The best way to deal with these folks is to assign them a role within the team and outline their responsibilities; you also can ask them if there's a specific area they're more interested in working on to see if you can ignite their passion.\n"Sometimes you can motive these folks by giving them a chance to lead, or making them responsible for something they care about. If they have a track record of laziness, though, you need to speak with supervisors and keep an eye on them, unfortunately," he says. \n3. I did it!Image by ThinkstockAll human beings enjoy recognition and praise, but some people crave that so much that they take credit for work they didn't do or claim achievements that aren't rightfully theirs, Maasik says. \n"Unfortunately, they are never so eager to take the blame if something goes wrong, are they? The best way to deal with this is to track and record who's working on which part of the project so that everyone can see how contributions are made. And if someone does insist on taking credit, then if failure occurs, make sure they get their fair share of blame, too," he says. \n[ Related story: 5 innovative ways to solve unimportant problems ]\n4.\tWhine with cheeseImage by ThinkstockNothing brings morale down faster than someone constantly criticizing, finding fault with or complaining about every aspect of a project. Whether it's how assignments were doled out, workloads, strategy -- no matter what, these folks seem to have a problem with it.\n"This behavior is so toxic; they spend more time whining about things than actually doing work. The best way to handle them is to first ignore their complaints, and then give them so much responsibility they don't have time to whine!" Maasik says. \n5.\tThe lone rangerImage by PexelsSome folks just work better alone -- and that's fine.But if they're jeopardizing your projects by going rogue, disregarding directions or trying to add their own solutions and touches, it might be better to sideline them, Maasik says. \n"Find some aspect of the project they can work on alone. If they work better solo, you'll get more productivity and work from them by allowing them to do their own thing, and save the sanity of the rest of the team," he says.