Cryptocurrencies, stablecoins and central bank digital currency open uncharted territory for the nascent economics of new digital money. This Pivot addresses the foundations of the monetary problem raised by Bitcoin and followers, starting with the game theory of Proof-of-Work as rent-seeking contest and a lively account of the different ways of trust that blockchain solutions and monetary institutions are meant to face. In so doing, the authors introduce the relevance of safe assets under the light of the principle of "no questions asked" that characterizes the monetary problem of the 2020s. Principles for regulation emerge in the perspective in which private issuers of digital coins are essentially issuers of demand deposits, and therefore bank-like entities. The potential role of central bank digital currency in the future monetary system is thoroughly discussed. Students and researchers in economics and finance, professionals and sophisticated readers may consider this book an essential guide to the challenging new dimensions of digital money.