The legitimacy of a system of dispute resolution depends intrinsically on the trust and confidence of its users in its decision-making processes, and that in turn rests on the general adherence of those processes to the values and principles that constitute the rule of law. While international arbitration has long been a close partner of the courts in sustaining the rule of law, some of arbitration’s key features and practices – such as its consent-based limitations, its predisposition toward confidentiality, its longstanding practice of permitting parties to unilaterally appoint arbitrators, and its philosophy that parties have no right to a right answer – mean that arbitration supports an attenuated model of the rule of law. That is largely the result of conscious decisions to forgo certain rule of law values in order to realize other goals. But the problem of rising costs and delays, underpinned by arbitration’s growing procedural rigidity and lack of agility, exacts a heavy price on arbitration’s users and their confidence in arbitration, without obvious returns. We must be cognizant of arbitration’s sacrifice in terms of rule of law values when seeking to advance other objectives, and regularly reflect on whether those gains are still worth their cost.