We all have a theory of change. When we ask our partner to change dinner plans for the evening, when we approach our professor to change the grade for a class, when we go into a company and try to change its sustainability strategy, we are working from a personal theory of what needs to change and why, and, importantly, how change takes place. That theory reflects how we see the world and how we engage with it. It defines who we are and how we will accomplish our life’s work. For example, when I was a house builder before I was a professor, I learned that I could lead my work crew by fear, by being liked, or by being respected. For me, the best option was the third because it most closely fit who I was, and that was a major factor in my success in house building. As Heraclitus said, “Character is destiny.”