The role of public health authorities is to protect, assess and ensure the health of people and communities. This chapter focuses on the role of public authorities in surveillance, the development and implementation of Incident Response Plans as well as in communicating risks to the public. The person in charge of the communications may be the one regularly in charge of the authority’s public communication. Such public participation can also serve to generate political initiatives and interest in waterbody management towards preventing blooms. For drinking-water supplies as well as for recreational sites or workplaces, surveillance should start with site inspections to assess the risk of cyanobacterial blooms, based on historical events and environmental conditions that lead to cyanobacterial bloom formation. Where the responsible authority is involved in surveillance monitoring, it may already be positioned to include cyanobacteria or even cyanotoxins.