This publication summarises results for all of Europe's native freshwater species of mollusc and for a selection of terrestrial mollusc families. About 44% of the freshwater molluscs and 20% of the selected terrestrial molluscs are threatened with extinction at the European level as a result of threats including pollution, dams, and water extraction (mainly for agriculture and drinking purposes) for the freshwater ecosystems and urbanisation, agriculture and recreation activities for the terrestrial molluscs.