Bilateral and multilateral investment treaties, such as NAFTA, give foreign investors substantive rights—such as freedom from expropriation—as well as the right to sue host governments for violations of the substantive rights enumerated in the investment treaties. In the last five years, the number of arbitrations arising under investment treaties has skyrocketed; billions of taxpayer dollars are at stake and government conduct, which would otherwise past domestic muster, is subject to enhanced international scrutiny. Given this recent development, arbitral tribunals are testing and evaluating a variety of international law rights for the first time. These private tribunals consider legal issues that impact the international economy, public policy, and international relations, but they do so in a vacuum largely because of gaps in the academic literature and confidentiality obligations that prevent public decision-making. Substantive obligations in investment treaties are remarkably similar; notwithstanding these similarities, in the absence of valuable guidance from scholars or appellate bodies, arbitral tribunals have come to inconsistent decisions on the meaning of fundamental rights under international law. This Article recommends a framework for analysis as well as a series of reforms to prevent inconsistent decisions and to correct inconsistencies when they occur. These measures will promote the integrity and legitimacy of a private dispute resolution system with wide-ranging public implications.