As the world struggles with the rapidly evolving pandemic of novel coronavirus disease (COVID-19), evidence and experience suggest that low-income and marginalized communities in our global society will bear the biggest impact. Weknow this because, with our colleagues in Boston, Haiti, Uganda, and Sierra Leone, we have worked in under-resourced, overstretched, and overwhelmed health systems for our whole careers. We know we will see the devastating impact of this pandemic on those who are already marginalized; COVID-19 will amplify existing inequities, and we must act swiftly to leave no one behind. (Author introduction)