The way you stand when you're talking to others, how you move your feet, your hands, your eyes - even your eyebrows - says a lot about your commitment to a conversation and your underlying attitude. Your actions and stance can also affect how long you get to talk and how often you get interrupted. Even when you're seated, the position of your arms and legs provides a wealth of information about your mood and intentions, showing whether you feel dominant or submissive, preoccupied or bored. But tells aren't confined merely to conversations; when you are alone you are constantly shifting your body - and each movement, each gesture provides clues about your state of mind. In this book, Peter Collett, social psychologist and Big Brother's resident psychologist, introduces the reader to the fascinating concept of tells, showing how they work, where they come from and how to identify and interpret them. Whilst sensitizing readers to the motives and actions of other people, this guide also focuses on the messages that we unwittingly send, and the impact that these might have on those around us. The book offers a unifying vocabulary for understanding human communication and social influence - and an opportunity to read yourself, and others.