Asking this one question is the secret to getting a raise, says former FBI negotiator

This is the real secret to getting a raise: You need to make yourself critical to your boss's success. So before you go for more money, there is one key question you need to ask, former FBI negotiator Chris Voss tells CNBC Make It.

"Hey boss, what's going on that's really critical to our success that I can help with?" Another way to ask the question might be, "Where are we going and how can I help us get there?" says Voss.

Or, alternatively, "How can I be guaranteed to be involved in projects critical to the company's future?"

Asking one of these questions will, in and of itself, set you apart. "Let's recognize the circumstances. Nobody ever goes into their boss's office unless they want something," says Voss.

"Your boss, your employer knows the moment you step in the office, you want something from them. That's why a lot of bosses and employers see all their employees as being selfish, because the only time that they hear from an employee is when the employee wants something, and it's usually more money."

By learning what your boss' key objectives are, and then being instrumental in following through on achieving those goals, you are making yourself valuable, explains Voss.

Voss is the founder and CEO of strategy consultancy Black Swan Group, and prior to working in the private sector, he was the lead international kidnapping negotiator for the Federal Bureau of Investigation, the 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.

"Before you begin putting a price tag on yourself (or anything) you have to begin establishing value ... Anyone who quotes a price without having any idea of value involved is flying blind," writes Voss in a blog post he published on his business' website about negotiating a higher salary.

"One of the greatest things you can do to establish value with your counterparts is to genuinely position yourself as being committed to their future prosperity. In every negotiation your counterpart, on some level, is asking himself or herself 'What's in this for me?' How about a bright future?"

Instead of asking directly for a raise, find out how you can be the most useful, says Voss, who is also the author of "Never Split The Difference: Negotiating As If Your Life Depended On It."

Then, of course, once you determine your boss's needs, you have to follow through and make yourself useful. But that will establish the precedent to get a higher salary.

"Establishing your value to your current or prospective employer in this manner makes you much more valuable and makes it easier for them to pay you well. You'll be worth it," writes Voss in the blog post.

"Because your dedication is to making their life better, your life becomes better as a secondary result. That's the way you get more money next year and the year after and the year after at all your performance reviews — because you have been making your boss's life better," he explains to CNBC Make 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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