TURNkey held a Task 5.3 (Development of Decision Support System (DSS) for OEF and EEW) workshop on July 2 via videoconferencing, with more than 20 participants. The purpose of the workshop was to showcase current task progress, identify synergies among the task’s various working groups, and begin a preliminary discussion about the structure of Deliverable 5.3 (due September 2021, M28). During the first part of the workshop, groups from University College of London, Eucentre, and University of Strathclyde presented the preliminary findings of their work on the development of DSSs for the Operational Earthquake Forecasting (OEF) and Earthquake Early Waring (EEW) across a wide variety of applications, including schools, ports, warehouses, and bridges. The second part of the workshop involved a productive discussion among all participants covering topics such as the practical implementation of the DSSs within the TURNkey platform.