Some of the most difficult toxic people to deal with at work are those who are highly insecure, according to executive coach, author and workplace psychology expert Stefan Falk.

"While feeling insecure is natural, problematic behaviors can develop when people consistently attempt to conceal or compensate for their self-doubt," he writes in an article at CNBC.com. 

What kinds of problematic behaviors? There are several that Falk says he's seen repeatedly in his 30 years as a leadership consultant.

To begin with, deeply insecure people tend to obsess over what others think of them and that can make them very hesitant to state an opinion, make a decision or commit to a course of action. "They frequently try to change the direction of projects and meetings," he writes.

If that isn't bad enough, they're liable to put others down and to talk about how busy and overloaded they are, both an attempt to make themselves look and feel important. Perhaps worst of all, Falk writes that highly insecure people can be "paranoid meddlers who make you question your every move."

If you have someone like this in your workplace – or your personal life – it's natural to feel frustrated. But, especially when you're the boss, anger and ultimatums are not the most productive way to deal with an insecure person.

Instead, Falk suggests nine simple steps for improving relations with a highly insecure person. They're all useful, but these are my favorites.

1. Spend a lot of one-on-one time

I know, I know – you would rather be dipped in honey and dropped on an anthill. Don't give in to the understandable impulse to avoid the insecure person whenever you can.

A lack of one-on-ones is why strategies fail in general, Falk writes and one-on-one meetings with an insecure person can be especially valuable. First of all, they're an opportunity to address some of their uncertainties, helping them feel a little less insecure.

Even more important, they're a chance for you to get to know the insecure person. The better you know them, the more you'll be able to understand what sorts of things trigger their most toxic behaviors and which situations allow them to respond better.

2. Be very honest about what you know and don't know

Insecure people worry a lot about getting things wrong and they will find any gaps in what you have to say, Falk warns. To ward this off before it happens, he suggests communicating information to them in a specific order.

Start with the things you know for certain, and say so. Next say the things that you believe to be true but don't know for a certainty and acknowledge that. Finally, talk about the things you don't know and don't have enough information to have an opinion about.

This meticulous honesty will reassure the insecure person and they won't be as tempted to engage in a game of gotcha with you.

3. Make it clear that you are not a threat

"You want them to think of you as an ally, not a rival," Falk writes. To achieve this, he suggests giving them compliments and expressing gratitude for what they do.

If they share information or useful guidance, tell them that you appreciate learning from them. This will tell them that you respect their expertise and may help ease some of that insecurity.

4. Find some compassion

Dealing with a highly insecure person can be infuriating. But keep in mind that their own deep feelings of insecurity and inadequacy are more than enough punishment for whatever annoyance they're causing you. Think about how awful it must be for them to feel that way about themselves all the time.

In my new book Career Self-Care, there's a whole chapter devoted to different types of toxic people and how best to deal with them. It's also true that most of us, at one time or another, have behaved like a toxic person and made life difficult for who have to deal with us.

Keeping that reality in mind will make it easier to treat a highly insecure person with understanding, grace and even a little wisdom.

Inc