In unpacking credit relationships and payments over the past 1000 years in addition to how technological innovations are shifting the credit relationships/payments landscape – from barter, commodity money, single layered to dual-layered financial money systems and from CBDC to stablecoins – this book systematically explores the various techniques that have been introduced in an attempt to improve the organisation, efficiency and stability of the IOU economy as a way to mitigate or prevent the universal challenge of the IOU economy from binding. In doing so, the book first unpacks how credit relationships, payments and economic life have developed throughout history, and sheds light on how the adoption of various techniques have led to greater efficiencies in payments across time. In addition, the book also explores how technological innovations are shifting the credit relationships/payments landscape. Subsequently, the book demonstrates how the adoption of five major techniques have to a large extent mitigated (but not eliminated) the threat of the universal challenge of the IOU economy from arising. With this, the book also envisages that the adoption of systems of financial accounts provides a didactic framework for those who are interested in studying topics in credit relationships and payments at an intermediate/advanced level (e.g. masters level university students, academics etc.).