As a business owner, your voice is one of the most powerful tools you have at your disposal. With nothing more complicated that your words you can close sales, negotiate deals,motivate employees, and clinch investment. But with great impact comes great danger. Anything that can radically improve your fortunes if employed well can also profoundly undermine your effectiveness when used poorly.

So what are the ways we most often go astray when communicating? That’s the topic of a quick but enlightening TED talk by author and The Sound Agency founder Julian Treasure. In it, he outlines the ways poor communicators end up alienating their listeners and eroding the power of their voices.

Want to be a great communicator with the ability to use your voice to change others’ behavior? Avoid his “seven deadly sins of speaking” at all costs.