**Coping with Corona (CoCo): Understanding individual differences in well-being during the COVID-19 pandemic** The COVID-19 pandemic not only poses major threats to people’s physical health but also to their well-being. To manage the pandemic, governments around the world have mandated policies that restrict people’s activities and limit social contact with others. Importantly, individuals differ in how they cope with these social challenges psychologically. The Coping with Corona (CoCo) Project aims to predict (build up theoretically derived and data-driven prediction models) and understand (unpack mediating situation selection, interpersonal perception, and emotional co-regulation processes) individual differences in well-being during the pandemic. These goals will be pursued by a comprehensive mega-analysis of existing data and large-scale international smartphone-based assessments (including experience sampling of everyday feelings and thoughts, mobile sensing of everyday social behaviors and contexts, and personalized feedback). The CoCo team integrates interdisciplinary expertise of leading researchers in the fields of personality, relationship, developmental, network, and behavioral data science. This project will generate insights of empirical, theoretical and practical importance. Specifically, results provide a rich description of how different people cope with pandemics, and novel insights on person-environment transactions that explain these differences. This will constitute a sorely needed step towards the large-scale availability of personalized tools to foster psychological resilience in individuals, groups, and societies in the wake of pandemics.