This work will deliver a review of cost estimates for the regional / global (supranational) activities needed to improve health security preparedness and protect the world from health emergencies like epidemics and pandemics. Working in collaboration with the World Health Organization (WHO) and academic partners at Duke University, this project will deliver evidence to inform new WHO guidance and policy recommendations, Government of Twenty (G20) negotiations, and related policy negotiations prior to the 75th World Health Assembly and beyond. The COVID-19 pandemic has highlighted the need for such work, with experiences over the past two years showing the importance of health security preparedness across country, regional and supranational levels. This work will complement ongoing WHO efforts to detail cost estimates for country-level resource needs for such preparedness activities. In doing so, this research will address five key issues related to determining cost estimates for pandemic preparedness and response reform: 1) Locating current and future budget / costing requirements at supranational and regional levels; 2) Detailing 'supranational' from 'regional' and 'national' activities; 3) Address the key knowledge gap around efficiency and effectiveness at the interface between national, regional and supranational levels; 4) Locate activities contributing to 'global common goods for health', and; 5) model subsystem investment prioritization strategies that can best realize these common goods for health in pandemic preparedness and response.