The State of the Arctic Freshwater Biodiversity Report (SAFBR), is a product of the Circumpolar Biodiversity Monitoring Program (CBMP) Freshwater Group of the Arctic Councils Conservation of Arctic Flora and Fauna (CAFF) Working Group. The SAFBR provides a synthesis of the state of knowledge about biodiversity in Arctic freshwater ecosystems (e.g., lakes, rivers, and associated wetlands), identifying detectable changes and important gaps in our ability to assess biodiversity across a number of Focal Ecosystem Components (FECs; see Box 1): fish, benthic macroinvertebrates, zooplankton, planktonic algae, diatoms (algae), and macrophytes. The overall goal of the SAFBR is to assess the current status and trends of freshwater biodiversity of FECs across the Arctic on a circumpolar scale.