An unprecedented pandemic, COVID-19 is currently hitting the world. After the initial outbreak in the city of Wuhan, Hubei province, COVID-19 is under control in China, with a few small waves caused by imported cases, of which have been stopped in China in 2–4 weeks, with between several cases and hundreds of cases per wave. We have seen clear peak–valley intervals with these small waves. It is crucial to understand why and how China has reached such success because it might help other countries. For COVID-19, we believe that active case finding at the community-level has been the key for China’s achievement. Since the 2003 outbreak of severe acute respiratory syndrome (SARS), health-care reform in China has been focused squarely on community-level capacity building, which compares with countries where community surveillance systems are not ideal.