Source: This article was originally published on CNBC.

Written by: Courtney Connley, CNBC Make It

Many professionals will probably recognize this situation: You go to a meeting or an event and, assuming that everyone there already knows you, or that you’re playing a minor role, you introduce yourself with your first name—or not at all.

No big deal, right? Wrong. I see it happen all the time, and it’s terrible. Your identity is an important piece of information for context in any business situation. Making a proper business introduction is key.

It drives me crazy when people fail to say their full names during a business introduction. But worse, this blunder could be hindering your professional advancement. Not stating your full name at the beginning of a business encounter essentially announces, ‘I don’t matter,’ or ‘I lack confidence’—or both.

A failed introduction is not just first-impression poison, but it can be a career killer, because who wants to listen to a person who doesn’t believe in themselves?

This was first pointed out to me 10-years ago when bestselling author and financial advisor Suze Orman scolded me for making this mistake during a speech. After I left the stage, Orman grabbed me and said, “You didn’t say your name!”

I protested that I had been introduced, but Orman said it didn’t matter. “Even when you think people know who you are, say your name—both first and last. Own your name and you own the room.”

I took Orman’s advice to heart. Recently, I spent a day coaching MBA students. The event included a Q & A, and I watched person after person take the mic and say, ‘Hi, umm, my question is blah blah…’ As each student came forward, I sat there thinking, who is going to hire you if you can’t even introduce yourself properly?

Please take this advice about your name. I promise you’ll see an impact on you and everyone in the room right away—and eventually on your career.

Suzy Welch is the co-founder of the Jack Welch Management Institute and a noted business journalist, TV commentator, and public speaker. Through its online MBA program, the Jack Welch Management Institute transforms the lives of its students by providing them with the tools to become better leaders, build great teams, and help their organizations win.