ITU US President Joe Biden recently announced a goal for 70 per cent of the adult US population to have received at least one COVID-19 vaccine shot by July 4. Cities are playing a key role in this historic vaccination effort, not only in terms of logistics and administration but also with respect to the critical component of resident engagement. To maximize vaccine uptake, local governments are working to mitigate any resident concerns; to counter misinformation and distrust; and to clear up confusion about practicalities. To do this effectively they need to understand – in close to real-time and at scale – how citizens are feeling about vaccines.