Researchers and leaders have looked for the secret to successful leadership for centuries. Dozens of new books each year promise to deliver the answer. We decided to examine this question empirically, and when we did, we found that the greatest predictor of success for leaders is not their charisma, influence, or power. It is not personality, attractiveness, or innovative genius. The one thing that supersedes all these factors is positive relational energy: the energy exchanged between people that helps uplift, enthuse, and renew them.