I work at OpenTable, the worlds largest provider of online restaurant reservations. You may have used our app to book a table at a fancy restaurant, or maybe you've worked at one of those restaurants and used our software. Since joining the design team, I have become one of the least fun people to dine out with. Just ask my wife. I used to be fully engrossed in our conversations, but now when we go out for a meal, I keep one eye on her, and one eye on the host, server, and kitchen staff to see how they deliver their unique style of service. I will share with you some of the many hidden interactions that go on behind the scenes in a restaurant. Through these stories you will learn how many restaurants gather information about their diners in order to promote their own agenda, while others choose to use that information in order to create rich, immersive experiences. Finally, I will share principles that will help you know when the use of personal information is proper, and when it is questionable.