The National Mooring Network Facility (formerly known as the Australian National Mooring Network (ANMN)), is a series of national reference stations and regional moorings designed to monitor particular oceanographic phenomena in Australian coastal ocean waters. There are nine current sub-facilities, including five regional sub-facilities. Inactive sub-facilities include: Ningaloo Moorings - WA, Deep Water Waves - Qld, Larval Fish and Acoustic Observatories. The current sub-facilities are: a) Queensland and Northern Australia b) New South Wales c) Southern Australia d) Western Australia e) Victoria f) National Reference Stations (Coordination and Analysis) g) Acidification Moorings h) Wave Buoys i) Marine Microplastics The National Reference Stations were first established in the 1940’s and are the backbone component of the observing system. Extended by IMOS from three to nine sites around the entire Australian continent, the stations report integrated biological, chemical and physical oceanography time series observations, upon which more intensive local and regional scale studies can be referenced against. The regional moorings monitor the interaction between boundary currents and shelf water masses and their consequent impact upon ocean productivity (e.g. Perth Canyon Upwelling; Kangaroo Island Upwelling) and ecosystem distribution and resilience (e.g. Coral Sea interaction with the Great Barrier Reef ). Operation of the network is distributed between several operators and coordinated nationally. The Acidification Moorings are co-located (or nearby) at three of the National Reference Stations, and provide key observations to help us understand and address the problem of increasing ocean acidification.