In the decades since, Marc has led large research teams and raised tens of millions of dollars to investigate the roots of emotional well-being. His prescription for healthy children (and their parents, teachers, and schools) is a system called RULER, a high-impact and fast-effect approach to understanding and mastering emotions that has already transformed the thousands of schools that have adopted it. RULER has been proven to reduce stress and burnout, improve school climate, and enhance academic achievement. This book is the culmination of Marc’s development of RULER and his way to share the strategies and skills with readers around the world. It is tested, and it works.