In The Fourth Branch: Reconstructing the Administrative State for the Commercial Republic Brian J. Cook confronts head-on the accumulating derangements in the American constitutional system and how the administrative state has contributed to the problems, how it has been a key force in addressing the troubles, and how it can be reformed to serve the system better. The Fourth Branch is anchored in a powerful theory of regime design that guides a freshly comprehensive account of the historical development of successive political economies and administrative states in the United States and provides the normative grounding for more far-reaching constitutional change. Cook calls for a decisive, pattern-breaking response in the form of a constitutional redesign to accommodate a fourth branch, an administrative branch. The Fourth Branch shows that the creation of a fourth administrative branch is consistent with the history and traditions of American constitutionalism. Far more than that, however, the addition of a fourth branch could enhance American constitutionalism by making the separation of powers work better, increasing the likelihood that deliberative lawmaking will occur, strengthening civic capacity and public engagement in governance, and improving both accountability and coordination in the administrative state. By stressing that the administrative state in its current form is both biased toward business and seriously undermined by subordination to the three constitutional branches, Cook contends that neither abandoning the administrative state nor more deeply constitutionalizing or democratizing it within the existing constitutional structure is sufficient to fully legitimate and capitalize on administrative power to serve the public interest. Rather, Cook argues that it is imperative to confront the reality that a fundamental reordering of constitutional arrangements is necessary if the American commercial republic is to recover from its growing disorder and progress further toward its aspirations of liberal justice and limited but vigorous self-rule.