Book section: Via peer-to-peer lending, notaries mobilized immense amounts of capital in France up into the 1930s. They did so despite a thriving stock market, widespread banking with branches, and the existence of an effective lender of last resort. Using detailed evidence on their careers and their businesses, we analyze their training, their successes and failures, how they were regulated, and how they dealt with political and economic crises. What we uncover teaches broader lessons about the misconceptions surrounding modernization, financial development, and the reputational models that economists rely upon to explain informal dealings.