The advent of new digital currencies has challenged our notions about money, its function and purpose and our faith in the financial and banking structures that underpin its legitimacy. Oonagh McDonald examines the challenges, opportunities and threats that cryptocurrencies pose to existing fiat currencies and their potential to change how global finance operates.

Beginning with Bitcoin, she charts the rise of cryptocurrencies over the past decade, including the failures of existing regulatory frameworks and the many fradulent initial coin offerings. The potential for Libra, Facebook’s blockchain-based payment system, is considered in depth. The book examines the motivations of central banks as they become increasingly interested in the opportunities for an alternative global stable digital currency and assesses their experiments with blockchain, smart contracts and digital tokens. The future of cash is also considered. The book concludes that notions of trust and credit will ultimately protect commercial bank money from the threat of new digital currencies.