My aim in this essay is to argue for a better moral-conceptual framework and for institutional innovation in preparation for the next pandemic. My main conclusions are as follows. (1) The primary moral principle that should guide responses to the next pandemic is the duty to prevent and mitigate serious harms. (2) A proper understanding of the moral foundations and scope of the duty to prevent and mitigate serious harms requires rejecting both Extreme Nationalism and Extreme Cosmopolitanism. (3) A better response to the next pandemic requires transforming the moral landscape through institutional innovation by developing an international institution that can perfect indeterminate duties (i) by identifying duty-bearers, (ii) by specifying their duties to provide medical resources and other forms of aid, (iii) by allocating the specified duties to various public and private entities in such a way as to ensure effective coordination and that the costs of providing aid are fairly distributed, and (iv) by providing effective mechanisms for compliance with the specified duties. (4) Institutional innovation is morally required, regardless of whether the harm prevention and mitigation duties of the better-off are duties of justice or of beneficence, because without institutionalization, some duties of justice, including those requiring the prevention and mitigation of serious harms, suffer some of the same indeterminacies that are present in duties of beneficence.