The United States Constitution, as well as those of many of the states in the Union, contain extensive and well known categories of fundamental rights which are protected against the assertion of governmental power. These fundamental protections are derived from the Constitutional documents themselves or are extracted from ancient rights and customs recognized at the time of the founding of the Republic. They provide substantial protection of property, of life and liberty interests of persons against the state, but have traditionally offered far less well defined protections of economic, social or cultural rights except to the extent they might be extracted from constitutionally derived protections against discrimination against a growing list of recognized categories—among them race, religion, ethnicity, sexual preferences. At the time of the founding of the Republic there was a near perfect identity between the institutions that exercised governance power and the scope of the “higher law” that constrained such exercise through the interposition of fundamental norms written into or extracted through law. But this ancient system, quite potent and adequate for the age in which it was created and reached its greatest stage of development, might be less responsive to modern forms of the organization of politics, economics and social life within the Republic. The development of the great structures of administrative regulation and organization in the 20th century, and the substantial governmentalization of private enterprises (especially enterprises operating in corporate form), has created certain disjunctions between those who exercise governance authority and the reach of constitutional protection against abuses of the exercise of governance power. This paper considers whether and to what extent—formally or functionally—the traditional constitutional constraints on government might be asserted against non-governmental authorities exercising governmental power. The paper first considers the conventional approach and traditional understandings of the limitations of the application of constitutional constraints against private actors asserting governmental authority. U.S. jurisprudence draws a fairly hard line between public and private actors, whatever the functional effect of their actions. The law in that respect has been fairly stable. That, combined with the traditional narrow scope of reading fundamental rights protections into the U.S. or state constitutions, makes the possible scope of application of constitutional constraints directly difficult. The paper then considers possible avenues for creating regimes that effectively transpose at least functional constitutional obligations onto private actors. There are several avenues worth considering. First, either federal or state legislation can transpose constitutional obligation against states into legal obligations that may be asserted against enterprises. Second, corporations could be encouraged to adopt these duties as a matter of internal governance and in their contracts with their stakeholders. Finally, an international law-norm approach will be considered. The limitations of these approaches will then be considered, including among them the possibility that corporations can challenge such legal regimes as violations of their own constitutional rights against governmental interference, that the complexity and limitations of effective applicable scope may make the approaches unworkable, and lastly that they will have little effective scope of remedy.