Lunch interviews happen quite frequently.  The job might be confidential, interviewers might not have the time in the office, an employer might want to see your social skills or they might want to impress you.  Whatever the situation, you are being evaluated and you must be prepared.  Here are a few dos and don't to follow:1.  Do some homework on the restaurant.  You can use this information to start a conversation or connect with the interviewer.  Does it have a history, why does the interviewer like it etc.2.  Don't become comfortable.  If the interviewer is being friendly and affable, you can certainly be less formal.  Just remember, it's still an interview.3.  Turn off your cell phone and put it away.4.  Don't start selling yourself.  Whatever the reason, lunch is still a social setting.  Follow the lead of the interviewer.  Listen and ask questions, if appropriate.5.  Don't over talk.  Keep any personal answers short and business answers to the point.6.  See what the interviewer orders and follow that.  Don't order the most expensive item and skip dessert.7.  No matter what happens, remain composed and don't ever be rude to the wait staff.8.  Be on time.