This book examines the effect of banking on the real economy and society, focusing on banking supervision as the decisive factor in steering banking activities and determining the social outcome of the game of finance.  Banking is like a cardiovascular system for our society. If it functions correctly, it allows the economy to operate smoothly. On the other hand, if it malfunctions it becomes a doomsday device. This creates an asymmetry of risks - the asymmetry between the potential dire consequences and the modest rewards of accepting those risks.  Banking was one of the critical technological factors enabling the transition from the middle ages and the creation of modern society. However, while today it contributes little to economic growth, its malfunction has a profound and lasting adverse impact. The book explains why, how and what. Why is it important to keep tight supervision of the banks? How can banking supervision improve stability, not only of the financial system but also of the whole human society? What went wrong with the regulation in the past?