Significant innovations in communications technologies, along with enabling infrastructure, have periodically given rise to entirely new types of firms and markets. Such far-reaching changes in firm structures and markets took place both in the late nineteenth century, as very large industrial firms took shape, and in the twenty-first century, as highly digitalized platform firms emerged. The first of these metamorphoses led to the development of a set of general principles and a body of tax laws, profit allocation rules and regulations, guidelines, treaties, and dispute resolution mechanisms (collectively, an ‘international tax system’) that would govern international taxation for a century; the second of these metamorphoses has necessitated far-reaching changes in this system. The institutions charged with adapting the international tax system to more effectively and fairly tax highly digitalized platform firms have developed an ambitious set of measures (‘Pillar One’ of the OECD’s ‘Pillar One-Pillar Two Solution’) that has garnered considerable support among many European Union (‘EU’) member states. First and foremost, Pillar One provides for the reallocation of a potentially sizeable portion of in-scope multinational firms’ consolidated pre-tax income to market jurisdictions, where consumers and users reside. In concept, this profit reallocation rule would apply to all firms, with both traditional and platform structures, above certain stipulated revenue and profitability thresholds. However, if implemented, Pillar One would not achieve its stated purposes. Pillar One is a heavy-handed, formulaic and singular approach to a problem that requires considerably more nuance. Separate sets of new profit and revenue allocation rules applicable to centralized multinational platform firms and decentralized multinational platform firms, respectively, would be more efficacious and more sustainable.