It's well known that good communication is the foundation of any successful relationship, be it personal or professional. It's important to recognize, though, that it's our nonverbal communication—our facial expressions, gestures, eye contact, posture, and tone of voice—that speak the loudest. The ability to understand and use nonverbal communication, or body language, is a powerful tool that can help you connect with others, express what you really mean, and build better relationships.