In far too many cases, recommendations of forensic reports on previous pandemics were ignored. Substantial weaknesses in the preparation by public health authorities and governments increased the health and economic costs of the COVID-19 pandemic relative to what they would have been if pre-existing recommendations had been followed and a wider set of plans had been put into place. We discuss parallels between the lack of preparation of financial system regulators prior to the global financial crisis and the lack of preparation by public health authorities and governments prior to COVID-19. These parallels relate to: required stocks (of capital or equipment), data collection and sharing, lending facilities, stress testing and war games, early warning indicators and systems, contagion from abroad, operational risks, a system-wide approach (including effects on the real economy), models incorporating the heterogeneity of individuals, and effects on less-regulated parts of the system. The recent COVID-19 crisis has demonstrated that, apart from the direct economic consequences from illness and death from the virus, the main costs have been due to the varying degrees of preventative measures taken by the public, firms, and governments that directly impacted health, as well as social, economic, and financial activity. We make recommendations for carrying out post mortems on the COVID-19 experience, planning for future pandemics, and establishing transparent and accountable governance systems. We then propose the use of regular, combined health, economic, and financial stress tests and exercises/war games in preparing for future pandemics and other major environmental shocks.