Recent years have seen the flowering of a new literature on the economic nature of firms marked by a concern with their internal organization and contractual characteristics. Related literatures on the principal-agent problem and the theory of financial markets have also contributed to a better understanding of firms as economic institutions. However, the place of the concept of the ownership of the firm is poorly developed in most of this literature, with many writers either ignoring the concept entirely or arguing (...) that it is of no importance. The purpose of the present article is to point out that the concept of ownership of firms is crucial to an understanding of internal governance issues. Most economists implicitly presume that firms must be ownable and saleable if they are to be operated efficiently, and recently this viewpoint has been made more explicit by writers such as Jensen and Fama and Williamson. Their point of view is to some degree at odds with views of the firm as a coalition, which frequently appear in the same literature, and even more fundamentally in conflict with conceptions of the firm as an association or polity within which greater or lesser degrees of democracy in governance may be pursued. The first purpose of this article is to show that the incompletely articulated position of the leading authors on the economics of organization is that the firm is a commodity and must be so for purposes of efficiency. (shrink)