"Tells" are actions which reveal valuable information about what people are really thinking or feeling. They are used regularly when playing poker, but Peter Collett takes it a step farther and applies the usefulness of "Tells" to everyday life. He talks about tells used to show dominance, submissiveness, sexual signals, tells used while smoking, political tells, international tells, etc.
Overall, I found this book to be a really interesting read. At times, the author became repetitive or stated the obvious, but this book was packed with tons of little interesting facts. It was a fairly quick read, and quite rewarding and entertaining as well because each time I would pick it up, I could find people around me who were using postures or other "Tells" that had just been described in the book. I'm now much more aware of the signals that I send out as well as those that others send out. Recognizing and deciphering these tells adds a whole new dimension to every social interaction/observation I have. Of course, this book won't teach you to read minds, but when accompanied with good sense and intuition it can make your life a little bit more fun.