This report summarizes the findings of the Rapid expert consultation on environmental surveillance of SARS-CoV-2 in wastewater that was organized by the WHO European Centre for Environment and Health on 23 July 2020 in a virtual format. It aimed to facilitate a rapid exchange of current knowledge, experience and practices among countries that are in the forefront of research and environmental surveillance of SARS-CoV-2 in wastewater. Such surveillance can be employed as a complementary tool to clinical surveillance of COVID-19. It provides supporting information to obtain an ample picture of occurrence of infection and take decisive public health response actions. While the consultation was able to take a valuable “snapshot” of current knowledge, approaches and experiences, there are a number of open or emerging practical questions that need to be looked at before promoting environmental surveillance at scale.