This book explores a most central phenomenon in our contemporary businesses and organization, the growing complexity in business. Economic growth and growth of complexity always have been inseparable, but the last decennia the growth of complexity appears to outrun our growth of knowledge and understanding. For success and continuity, the modern firm in the developing complexity of its markets and societal contexts must have the capacity to master and exploit a commensurate level of complexity in its internal organization. This book is the first of its kind to help the reader to understand the different types of complexity and the different concepts and tools to deal with each of them in business administration, strategy, and organization. This book offers the reader a fresh perspective on conventional concepts and tools in the field of business administration and bridges these to new concepts as are being used to exploit new complexities. In the process, the reader becomes familiarwith the rich cybernetic concept of information, as a basis for the information-based organization and to master big data. With that complex decision-making is clarified and a fresh understanding of the core function of the organization, coordination, is offered for those who want to solve the issue of self-coordination. The book provides working examples but even more the strongest tool to master and to reduce complexity: a deeper and broader understanding of what is going on beneath the surface of what we experience daily. This book builds on Herbert Simon’s hypothesis of simplicity: ‘to use the simplicity of process to deal with the complexity of state.’