Freeganism is the practice of reclaiming and eating food that has been discarded. Freegans and Freeganism are often seen as part of a wider "anti-consumerist" ideology, and freegans often employ a range of alternative living strategies based on limited participation in the conventional economy and minimal consumption of resources.

Freegans "embrace community, generosity, social concern, freedom, cooperation, and sharing in opposition to a society based on materialism, moral apathy, competition, conformity, and greed."

The word "freegan" is a portmanteau of "free" and "vegan"; not all dumpster divers are vegan, but the ideology of veganism is inherent in freeganism. Freeganism started in the mid 1990s, out of the antiglobalization and environmentalist movements. The movement also has elements of Diggers, an anarchist street theater group based in Haight-Ashbury in San Francisco in the 1960s, that gave away rescued food.

The manifesto pamphlet "Why Freegan" (written by former Against Me! drummer Warren Oakes in 1999) defines freeganism as "an anti-consumeristic ethic about eating" and goes on to describe practices including dumpster diving, plate scraping, wild foraging, gardening, theft, employee scams, and barter as alternatives to paying for food. Motivations are varied and numerous; some adhere to freeganism as an extension of anarchism or other anti-capitalist tendencies, or simply for environmental reasons, some for religious reasons, etc. A short 2008 documentary film, Bin Appetit, gives reasons people become freegans.