The opponents and proponents of competitive brokerage commission rates for the New York Stock Exchange have, for nearly a decade, been dueling in the hearing rooms of Congress and the Securities and Exchange Commission (SEC). The contest developed because financial institutions, in attempting to skirt the New York Stock Exchange (NYSE) and its fixed commission rates, had used a variety of trading practices that were sharply criticized by the government overseers of the securities markets. The securities industry, the government overseers, and scholars have debated what would be the most effective regulatory approach to improving the social performance of the securities marketplace. Would it be through initiating even more stringent federal regulation of exchange behavior? Or, would it be through selective deregulation to increase competition, particularly in the determination of commissions? Competitive forces might constrain and direct that behavior. The policy that has been developing would deregulate and restructure the marketplace to create a “central market system.” Competition would replace regulation to whatever extent may be possible, in determining both commission rates and the quality of marketplace services provided [6]. But, the contest has been long and often heated. From the thrusts and parries, there can be identified some fundamental issues concerning the economics of the stock exchange as a form of marketplace organization.