This book develops a general theory of managerial decision making on the basis of a few elementary postulates. It employs logic as the method of reasoning, systems science in general and the systemic YoYo Model in particular, as the intuitive playground. By doing so, the authors take individually background-based guesswork out of processes of decision making. All established conclusions are expected to be generally employable in real-life applications. At the same time, the book is user friendly to a wide range of audience, coincides with people's intuition, and provides applicable results and insights for practical purposes.