Decipher the unspoken vocabulary of body language. A tilt of the head, the crossing of legs, the buttoning and unbuttoning of a jacket, and other gestures can speak volumes about what a person is thinking or feeling. By learning to spot hidden emotional, social, and sexual messages, you can tell how a person is reacting to you, respond appropriately, and influence the outcome of any situation. Detect and send messages of friendliness and flirtation. Gain and maintain the upper hand in negotiations and arguments. Determine whether someone is lying, recognize boredom, and overcome defensiveness. By interpreting nonverbal behavior, you can improve your control over job interviews, business meetings, parties, chance encounters, and other everyday situations.