When faced with an urgent and credible threat of grave harm, we should take proportionate precautions. But what is it for a precaution to be “proportionate”? I construct a pragmatic analysis of consisting of four tests—permissibility-in-principle, adequacy, reasonable necessity and consistency—that could realistically be applied by a citizens’ assembly meeting online or in person. I apply these tests retrospectively to two examples from the COVID-19 pandemic—border closures and school closures—arguing that my account captures the key questions on which it is (...) both feasible and important to integrate expert input with democratic input. I then consider how we might try to manage the risk of future pandemics in a proportionate way. (shrink)