This book examines the institutional and cultural underpinnings of a financial puzzle: given that the overwhelming majority of retail traders lose money in financial transactions, why do we see ordinary people continuing to engage in trading? This phenomenon is analyzed by means of an ethnographic investigation of how electronic financial markets work. The book takes the perspective of the relationships among retail traders, institutional traders, and brokers. “Noise” investigates the social institutions that recruit ordinary people and support their participation into financial trading. Contrary to widespread assumptions, the book shows that professional and retail traders are not two completely separated categories. It analyzes how transitions are made between them, as intrinsic to reproducing the financial workforce. Based on direct observations and interviews with traders and brokers in the US and the UK, the book takes a close up look at the practical actions of trading, and at how these relate to the brokers’ actions. Using extensive interviews with traders, “Noise” sheds light on the rationales for taking up trading and continuing with it even if little or no gains are made. It shows how traders make sense of their financial actions and decisions in relationship to their social lives, challenging a utilitarian view about profit as the ultimate motive in trading.