This document summarizes research on the relationship between body language and personal perceptions of power and confidence. Nonverbal behaviors like posture, gestures, and facial expressions can influence how powerful and in control we feel. Specifically, taking up more space by expanding our bodies through open postures makes us feel more powerful and confident, increasing testosterone and decreasing stress hormones, while closed postures make us feel less powerful. The findings suggest we can influence our own self-perceptions and behaviors by adjusting our body language to be more open and expansive over time.