Responsibilities for traditional coast guard duties in Australia are distributed across various federal, state and community agencies. The de facto coast guard of Australia is the Maritime Border Command, a joint command of the Australian Defence Force and the Australian Border Force which works alongside the Australian Federal Police, the Australian Fisheries Management Authority, and the Australian Maritime Safety Authority. Each state and territory government have specific maritime safety agencies and police marine units. In addition, there are several private volunteer coast guard organisations which act as auxiliary search and rescue services and maritime safety educators with the largest organisations being the Royal Volunteer Coastal Patrol established in 1937, the Australian Volunteer Coast Guard established in 1961, and Marine Rescue New South Wales established in 2009.

A coast guard or coastguard is a maritime security organization of a particular country. The term embraces wide range of responsibilities in different countries, from being a heavily armed military force with customs and security duties to being a volunteer organization tasked with search and rescue without law enforcement authority. In most countries, a typical coast guard's functions are distinct from those of the navy and the transit police, while in certain countries they have similarities to both.