One sentence: Living is changing, and you need other people to help you solve problems.
This book teaches the four styles of management, how they are in conflict, how to use conflict constructively, and how to adapt to change in life. Problems that arise when one of the management roles are deficient and how to solve them are explained.
With a detour through the roles of trust and mutual respect, you learn how to communicate with all 4 styles and what type of person you need to complement your style. I think every manager should have the diagrams in this book on their wall.
I would have preferred a book that is not formatted as a dialogue, but it is of no great consequence: you still get a lot of information and understand it at the end.
To happiness, and beyond!