Toxigenic cyanobacteria are one of the main health risks associated with European water resources. They produce a wide range of potent toxins with adverse health effects on humans and animals exposed to them via drinking water, aquaculture and recreation. European research in the field has generated significant risk management capability, although this is regionally unbalanced. The aim of this COST Action was to transfer this knowledge and know-how to all European regions: widening awareness, spreading relevant technical competence, and sharing risk management expertise. The Action provided tools to end-users (public authorities, water utilities, aquaculture, tourism and recreation sectors) by pooling and coordinating expertise throughout Europe and harmonized methods and practices across Europe, thereby protecting public health, enterprises and investments. Over 150 partners (scientists, other professionals and companies), from 23 European countries, were participated in this Action. The main objective of this network was to increase, disseminate and harmonize capabilities across Europe for the risk management of cyanobacteria and cyanotoxins in water bodies, by establishing strong and synergistic links between academia, authorities, industry and citizens. NCSR “D” selected by the Action’s Management Committee as Action’s Grant Holder (Scientific Reperesentative: Dr. A. Hiskia, Grant manager: Dr. T. Triantis). Budget: 670K€.