This book provides an economic analysis of the stock exchange industry. It draws on theories from micro- and industrial economics to provide a detailed analysis of the industry structure, the strategic behaviour of key participants and a methodological framework for assessing the performance of stock exchanges. It provides an overview of the factors driving the consolidation of the industry, and examines the implications of ongoing changes in the regulatory environment. It investigates the functioning of securities exchanges and other trading platforms as firms, assuming an industrial organization perspective and focusing on the competitive behaviour of exchanges, regulation and governance arrangements and their impact on the structure of the industry.