This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book considers how the monetary arrangements affect the capital structure and focuses on the relationship between monetary arrangements and the capital structure. It also considers what we can learn about heuristics and the evolution of units of account and media of exchange. The book addresses interwar monetary fragmentation and the gold standard restored, the gold-exchange standard, considering the Great Depression as well as comparing that with a potential restoration of the gold standard, considering the Great Recession. It analyzes seventeenth century exchange banks, considering Amsterdamsche Wisselbank, and Stockholms Banco as two distinct cases. The book describes the co-evolution of units of account and media of exchange in the Baltic and North Sea region, studying the processes of establishing the value of money as a unit of account.