General cognitive ability, more commonly known as IQ, is the single best predictor of performance in a wide variety of jobs. But when you’re already in a job with lot of other smart people, and especially, if you’re a leader, what separates the great leader from the good leader? Emotional intelligence. In fact, emotional intelligence has been shown to matter twice as much as IQ and expertise. The best leaders have developed skills that help them understand people and how to get results through the efforts of other people. The most successful global companies are run by leaders who display attitudes that include self-confidence, self-control, achievement-orientation, empathy, and teamwork—all components of emotional intelligence.