In this article, the authors consider the impact of the institutional and market environment in which Canadian business operates on the structure of corporate and securities law. The authors argue that the linkages between markets and law have been neglected by scholars, judges, and regulators concerned with Canadian corporate and securities law, resulting in the adaption of approaches that are ill-suited to the Canadian environment. Canadian capital markets, for instance, are characterized by high levels of share ownership concentration, thin trading problems, intensive inter-corporate linkages, and possibly lower levels of efficiency. In sum, these factors make the problems occasioned by separated ownership and control (the Berle and Means corporation) much less acute in Canada than the problems of majority shareholder opportunism. These factors also suggest that regulatory initiatives should be structured in a way that distinguishes between the problems of large, intensively traded companies and smaller, thinly traded companies populated by retail investors. The authors consider these issues in the context of three case studies: the private agreement exception, poison pills, and a self-interested transaction.