Think of business dinner as an opportunity. People are more relaxed in the evening. The Official Workday is over. Let's start with the evening. But the last thing you want is for the food to get in the way. You can't enjoy a lobster and close a big deal at the same time. If you're smart, you can take advantage of relaxing attitudes and make the working dinner the wonderful opportunity to get business done.
Never let your food get in the way, and let your mind turn to business. Turn your cell phone off. Make sure other matters aren't interfering with the business. Don't be late, not a single minute late. If the other person's late, you just wait patiently. Make sure you're not lacking for conversation topics. Try keeping the conversation focused on your topic. One of the things that people enjoy doing is talking about themselves. So, if you are letting them shine a little bit, that will be great for your business.
Even though you should be prepared for tense situations, you'll find that a lot of the times your dinner partner will allow you to relax. Clearly this tactic is a smart one, because your colleague is comfortable doing business with you if you make them comfortable in general. The goal is to create a good rapport that will turn into a memory. And in this case, the rules get relaxed too.
It's a relaxed process, and one you'll welcome if it takes you a little time to get warmed up. This separation from the dinner is a good warm-up for the pressure of sitting around a table discussing business. But watch out that you don't stay too long at the bar. Be very limited in your alcohol. Recognize that this is a meal. You're going to put on your best impression, and you're going to do it because you're not feeling dizzy.