To a small business owner, one negotiation with a prospect can make or break the company. With so much at stake, quick rapport-building becomes a critical skill. And what is rapport? In business, it’s simply a framework for information transfer.

When you walk into that meeting, you need to know more about the people you’re meeting with than they know about you. That knowledge is power and provides a distinct advantage. Everything you know about the people who are there to evaluate you will impact how you approach them. It will guide you in knowing when and how to cause stress—for example, to ratchet up the level of concern about a problem you can fix—and when and how to counter that stress.

Taken together, the information you collect and behaviors you observe will give you what you need to establish rapport quickly. Here are tips to help you do that:

Come in with prepared questions. You are meeting with a customer in the property management business and you want to discuss professional services. You prepare a list of questions in jargon he would use to describe his biggest opportunities to make money and factors that impact his bottom line. It allows you to speak his language instead of asking him to educate you or speak your language.

Observe body language to detect signs of acceptance or rejection. When you are winning someone over in a negotiation, the person will do things like this:

Conversely, when you have pushed too hard or missed the mark in rapport-building, you will see some or all of these signs:

This article was written by Gregory Hartley and published in Bloomberg Businessweek magazine.