Orthodox financial theory often ignores the role played by managers' personal characteristics in their decision-making processes. However, as anyone with experience in the business world knows, managers' personalities are crucial in the choices they make. Indeed, it should be noted that firms do not make decisions, rather it is the managers who decide - either as a group or individually. This book explores the impact of managers' psychological profiles and life experiences on their financial decisions, taking the following key questions as starting points: Why do they commit mistakes? Why do they contract debt and issue shares? How do they choose the right amount of dividends to distribute? Why do they acquire other firms? Why do they sometimes choose to manipulate information and to commit fraud? As the book highlights, having insights into managers' psychology is essential to understanding their choices and predicting decisions made by competing firms.