As a tool to help people recognize emotions, the Mood Meter was first used in The Emotionally Intelligent Manager, a 2004 book by David Caruso and Peter Salovey. Later, Caruso and I built on that and developed it into the centerpiece of RULER, our evidence-based approach to social and emotional learning that currently is in more than two thousand schools and districts in the United States and in other countries, including Australia, China, England, Italy, Mexico, and Spain.
