Former FBI hostage negotiator: This surprising technique makes you look fearless in any negotiation

To give yourself the upper hand in any negotiation, go out of your way to show the opposition you understand how they feel.

Though it may seem counter-intuitive, showing empathy to your counterpart will help you get your way, former FBI negotiator Chris Voss tells CNBC Make It.

And in particular, understanding and acknowledging the concerns the other party may have about you is a sign of strength.

"A really good empathy statement actually includes you saying the other side's negative feelings about you. It actually makes you look fearless," says Voss, founder and CEO of strategy consultancy Black Swan Group and a former lead international kidnapping negotiator for the Federal Bureau of Investigation.

By articulating your counterpart's doubt, you are saying, "I know how you feel about me, and I'm not afraid."

Voss, who was also lead crisis negotiator for the New York City Division of the FBI and a member of the New York City Joint Terrorist Task Force for 14 years, says it makes you seem courageous and self-aware.

"In your eyes, your respect for me increases because I'm not afraid of the negativity, and I'm very honest about it, which means as far as you're concerned, I'm also not delusional," he explains.

Examples of empathy statements that take into account common negative feelings include: "It seems like I'm not listening to you," or "It seems like I'm not taking your interests into account," says Voss, author of "Never Split The Difference: Negotiating As If Your Life Depended On It."

Empathy does not require that you agree with the other person's perspective. It does not even mean that you like your counterpart.

"The FBI hostage negotiation definition of empathy doesn't have anything to do with like or agree or disagree. It just is. I can recognize how you actually feel," says Voss.

Additionally, in negotiation, empathy is not about making friends. It is simply a highly effective tool.

"I'm a mercenary. I love empathy not because I'm a missionary, not because I'm a nice guy. I love empathy because it helps me get my way," says Voss. Even sociopaths, those who have no conscience, use cognitive empathy because they know it will help them get what they want, notes Voss.

"Empathy makes you more effective; it saves time. The other side will come to agree with you sooner if they feel empathy from you," says Voss.

"For some reason, you care if I understand your pain. ... Empathy gets me what I want without paying for it for it. And that's the importance of empathy. I don't have to trade anything for it."

See also:

Former top FBI negotiator: This is the No. 1 secret to getting what you want

Warren Buffett uses this simple psychological trick to be persuasive and so can you, says influence expert

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