The Communities at Risk Register (CaRR) has been developed to provide an objective means of identifying risk and prioritising flood risk management activities at a Wales-wide, community level. It applies a standard methodology across all flood sources to calculate a theoretical ‘danger score’ that allows comparative risks to be quantified and ranked (from High to Low). The CaRR comprises a spreadsheet that identifies and ranks individual communities for, 1. a natural, ‘undefended’ scenario, and 2. a mitigated scenario (based on the presence of defences and flood warning). It is complemented by a GIS layer which defines the individual Community polygons and is attributed with danger scores, community rankings and other metric information.