Bertrand Russell defines power as the ability to produce intended effects. Robert Vecchio defines it as the ability to change the behavior of others. Dacher Keltner defines power as your capacity to make a difference in the world by influencing the states of other people. If Russell is right, then your every need, want, passion, cause, and ambition demands power. If Vecchio is right, then power inhabits every act of teaching, encouraging, parenting, storytelling, leading, and mentoring future leaders. If Keltner is correct, then my power changes your world, for better or worse. What if they're all right? What if power is all of the above? Then, at the very least, we'd all benefit from a better grasp of power.