Avant-garde (French pronunciation: ​[avɑ̃ɡaʁd]); from French, "advance guard" or "vanguard") refers to people or works that are experimental or innovative, particularly with respect to art, culture, and politics.

Avant-garde represents a pushing of the boundaries of what is accepted as the norm or the status quo, primarily in the cultural realm. The notion of the existence of the avant-garde is considered by some to be a hallmark of modernism, as distinct from postmodernism. Many artists have aligned themselves with the avant-garde movement and still continue to do so, tracing a history from Dada through the Situationists to postmodern artists such as the Language poets around 1981.

The term also refers to the promotion of radical social reforms. It was this meaning that was evoked by the Saint Simonian Olinde Rodrigues in his essay, "L'artiste, le savant et l'industriel", (“The artist, the scientist and the industrialist”, 1825) which contains the first recorded use of "avant-garde" in its now-customary sense: there, Rodrigues calls on artists to "serve as [the people's] avant-garde", insisting that "the power of the arts is indeed the most immediate and fastest way" to social, political, and economic reform. Over time, avant-garde became associated with movements concerned with "art for art's sake", focusing primarily on expanding the frontiers of aesthetic experience, rather than with wider social reform.