This book offers a comprehensive analysis of the evolution of equity markets in Canada and the United States with particular attention to the institutional and regulatory architectures that have shaped them. It begins by tracing the development and evolution of the U.S. exchanges and the emergence of securities regulation in the United States. The book then studies the boom years of the 1950s and 1960s, which came with the growth of mutual funds and a growing role by other institutional investors including pension funds and insurance companies. The study then explores the U.S. government’s pivotal role in fostering the growth of Nasdaq and the National Market System, which contrasted with Canada’s weaker regulatory environment. In addition , the book discusses how the failed merger between the Toronto Stock Exchange and the London Stock Exchange ultimately contributed to the consolidation of market power for the TMX Group—an entity that has achieved unrivalled dominance in Canadian security markets and operates under the effective control of most of the country’s leading commercial banks. This work is of significant interest to scholars, students, investors, and policymakers concerned with financial history, capital market structure, regulatory change, and the history of North American stock markets.