The first meeting of Working Group 1 (WG1: Early warning methods for detection of blooms, risk assessment, citizen science) will convene on March 12, 2025 in a hybrid fashion, online and at Sciensano in Brussels, Belgium. The current WG members and local stakeholders will engage in an informative session on the main action points of the WG and help shape the priorities for the WG during the remainder of the COST action. Under the guidance of Prof. Dr. Christine Edwards and Dr. Wannes Van Hassel, key topics, including current and future regulations, contemporary technologies, stakeholder engagement, and stakeholder needs will be presented and discussed. This meeting will help to organize WG members and scientific and dissemination activities to further progress toward obtaining the proposed outcomes of the CYANOCOST.