The best gifts aren’t about the object. The best gifts make us feel that we are deeply understood. “Ah! They ‘get’ me!” With her new book, The Four Tendencies, Gretchen Rubin has given us such a gift.

The book is an especially juicy read for those of us who enjoy taking personality tests like the Myers-Briggs (INTJs in the house!), and who adore Rubin’s previous best-selling works, such as The Happiness Project and Better Than Before. Rubin is a master at studying human behavior, looking for ways that we can leverage our natural tendencies to become our best selves.

In her latest, she boldly puts forth a new framework of personality types, based on how people react to internal and external expectations. She tested her theory on 600,000 people who took her online quiz. People tend to fall into four tendencies, Rubin notes: Upholders, Questioners, Obligers, and Rebels. I could immediately peg myself, my spouse, and one of my two children (still a little unsure about the other). But the IDing is just half the insight. Rubin then goes into the nitty-gritty on how to deal with each tendency, whether self, spouse, child, coworker, or health-care client (an interesting choice of category, I thought), as well as best career choices for each tendency. Whatever tendency we fall into, we can harness the strengths and shore up our weaknesses, and Rubin shows us how. Perhaps her most important point, in this age of media, is that “for an important message to be effective, it needs to resonate with every Tendency.” Rubin’s latest is a terrifically fun—and useful—read.