Structural change in container port operation and ownership over the past decade has seen the emergence of port-operating transnational corporations (TNCs). The emergence of the port-operating TNC requires a fundamental epistemological shift in reconceptualising the port, from a single, fixed, spatial entity to a network of terminals operating under a corporate logic. This shift is twofold. First, because under port reforms corporate entry occurs overwhelmingly at the terminal level, the terminal rather than the port becomes the relevant spatial unit of analysis. Second, although spatial theories of the firm represent a longstanding stream in economic geography, such theories have yet to find general application in port studies. Consequently, in addressing the interface between transport and economic geographies, the authors suggest a geography of the port-operating TNC as a potential bridge. A decade of privatization in the port sector has rendered the industry an appropriate empirical ground for enquiry into spatial theories of the firm. Evidence from Asian port systems and business networks are put forward in sketching a new research agenda.