In their new book, Leading Through: Activating the Soul, Heart, and Mind of Leadership (Harvard Business Review Press), former dean of Harvard Business School Kim Clark, his son, Jonathan, a professor of management at the University of Texas at San Antonio, and his daughter, Erin, a management consultant, call for the end of a power-focused leadership model and introduce a new approach: the “leading through” paradigm. This new leadership model consciously seeks to do good and to make things better; cares for people, helping them to thrive; and mobilizes people to solve tough problems. These three elements, they argue, are the soul, heart, and mind of leadership — and activating them requires careful attention to both the personal and the organizational dimensions of leadership. The following is a lightly edited excerpt from their book.