Working well with others is critical to professional success, yet many people struggle with "authority issues" that can block their progress. Professor Gruenfeld combines research on the psychology of power with the acting skills of the theater to illustrate how our nonverbal behavior affects how we are perceived in a hierarchy—far more than the words or arguments we use. In fact, she notes, our words account for only 7% of our argument's impact. The good news is that we can control how we are perceived by using our body language to influence others. From how we hold ourselves to how we speak, Dr. Gruenfeld explores the ways to "play high" when we want to be authoritative, and "play low" when it's more advantageous to be approachable. In the end, she notes, we're judged not on the quality of our argument, but on how we act and how we make others feel. Deborah Gruenfeld is a professor of leadership and organizational behavior at the Stanford Graduate School of Business. She received her BA in psychology from Cornell University, her MA in journalism from New York University and her PhD in psychology from the University of Illinois.