This paper examines contemporaneous and historical evidence on the structure of ownership and control of corporate sectors in developed countries to draw lessons for development of financial markets. It records the critical role that equity markets played in the ownership and financing of corporations at the beginning of the 20th century. It notes that this occurred in the absence of formal systems of regulation and that equity markets functioned on the basis of informal relationships of trust. These were sustained through local stock markets in the UK, banks in Germany, and business coordinators and family firms in Japan. The paper explores the concept of trust that is required to promote the development of financial markets.