The chapter explores the challenges and potential solutions in the realm of Decentralized Finance (DeFi), emphasizing the problem of ensuring trust and record accuracy in decentralized ledgers. It uses a hypothetical village ledger to illustrate these challenges, where rewriting transaction history poses a major risk. The chapter describes the Bitcoin White Paper as a potential solution to these problems, introducing a peer-to-peer monetary system that bypasses traditional financial institutions. Furthermore, it discusses the introduction of Central Bank Digital Currencies (CBDCs) and their necessity given existing digital payment systems. The chapter cautions against potential inefficiencies and regulatory challenges, arguing for a cautious approach to financial innovation. It touches on the concept of stablecoins, which aim to combine the stability of fiat currencies with the benefits of digital finance.