Book excerpt: No matter how old you are, where you come from or what you do for a living, the desire to have satisfying and meaningful relationships is one we all share. Relationships are key to everything we do, and the bonds and connections we make with others is what gives us the greatest sense of meaning, happiness, and fulfillment. Nothing interferes more with your ability to enjoy rewarding relationships than an inability to understand your own emotions and manage their impact on you and those around you. Emotional intelligence, the currency of the 21st century, is the essential skill set that separates those who fail in their personal and professional relationships from those who succeed.