ergence of platform competition and the shift from regulating outputs to regulating inputs have made it increasingly possible for regulatory authorities to determine value on the basis of actual market transactions. This shift implies that the theoretical and technological transformation of regulated-industries law com- mands, in turn, a similar transformation of the principles used to evaluate takings challenges to access regulation of network industries. Front-line policymakers, those in charge of implementing access regulations, have largely ignored these implica- tions. Therefore, the obligation to enforce these principles will fall to the courts as they begin to address the merits of takings challenges to this type of regulation. The emergence of platform competition and the shift to access regulation have made basing rates on market prices more feasible than ever before. Although we expect the level of competition in the relevant markets, which include local telephony, multichannel video programming distribution, and broadband services, to vary, the competition likely to emerge in each industry should be sufficiently robust to justify basing rates on market prices. We demonstrate in regulatory case studies in the following chapters how some types of access to networks necessarily require a permanent physical invasion, which adds a constitutional dimension that reinforces the economic analysis. PART III POLICY APPLICATIONS The Regulation of Local Telephone Networks In this part, we apply the framework developed in the earlier chapters to a series of current issues in telecommunications policy. The first issue, discussed in this chapter, is the regulation of local telephone networks. Chapter 9 examines how antitrust law has been applied to the telecommunications industry. Chapter 10 uses the framework we have developed to analyze the regulation of broadband networks. Chapters 11 and 12 examine one of the most high-profile recent issues in telecommunications policy: "network neutrality." A. The History of the 