This course uses models of monopoly and competition to investigate enterprise behavior and to consider implications for market structure and resource allocation. In addition to focusing on factors determining the number of market participants, the course examines the role of transactions costs, product differentiation, imperfect knowledge, and contestability in determining market outcomes. Special attention is given to issues of monopoly regulation and antitrust law in the United States and internationally. (ECON 0255) 3 hrs. sem.