The National Audubon Society is an American non-profit environmental organization dedicated to conservation of birds and their habitats. Located in the United States and incorporated in 1905, Audubon is one of the oldest of such organizations in the world. There are completely independent Audubon Societies in the United States, which were founded several years earlier such as the Massachusetts Audubon Society, Indiana Audubon Society, and Connecticut Audubon Society. The societies are named for 19th century naturalist John James Audubon.

The Christmas Bird Count (CBC) is a census of birds in the Western Hemisphere, performed annually in the early Northern-hemisphere winter by volunteer birdwatchers and administered by the National Audubon Society. The purpose is to provide population data for use in science, especially conservation biology, though many people participate for recreation. The CBC is the longest-running citizen science survey in the world.