Drawing from rich, multi-sited fieldwork and data collection, this research monograph offers an in-depth look into the financial market practices around the quantitative easing programmes of the European Central Bank and focuses on the uneasy role of modern central banks as active market participants. The author introduces concepts from social network theory and develops a novel method to study organisational networks in the context of financial markets. An analysis of the European Central Bank’s social, organisational and financial networks is sketched over the course of multiple chapters. The concluding chapters dive into documentary analysis and the extensive material from qualitative interviews with senior investment professionals about the strategies and adaptive processes around the lived experience of quantitative easing. The winner of the British Sociological Association’s prestigious Philip Abrams Memorial Prize, this book is a vital resource for social scientists researching organisations in financial markets, providing theory, concepts, empirical data and practical implications. It will be of interest to academics and graduate students in economics, sociology and management/organisation studies, as well as practitioners at central banks and in asset management.