COVID-19 vaccines have transformed the trajectory of the global pandemic. Since their introduction 16 months ago, health officials and their expert advisors have had to respond to rapidly emerging and evolving evidence and an array of corresponding policy questions, doing so at a relentless pace and under unprecedented public scrutiny. Using the COVID-19 vaccination program in the United States as its principal case study, this talk will examine how the deliberations of government expert advisory bodies have informed the work of public health agencies in translating evidence into policy in the design and implementation of vaccination efforts. It will highlight the challenges and conflicts that have arisen throughout this work, the ways in which values and value judgements have shaped the perspectives and recommendations of scientific experts, and how the international context of COVID-19 vaccination has influenced discussions of domestic vaccination policy.