Crass were an English anarcho-punk band, formed in 1977 which promoted anarchism as a political ideology, way of living, and as a resistance movement. Crass popularized the seminal anarcho-punk movement and advocated direct action, animal rights, and environmentalism. The band used the "Do It Yourself" approach to produce sound collages, graphics, albums and films. Crass also criticized and attempted to subvert the dominant culture with messages promoting feminism, anti-racism, anti-war, and anti-globalization.
Crass practiced their "direct action" philosophy by spray-painting stencilled graffiti messages around the London Underground system and on advertising billboards, coordinating squats, and organising political action. The band also expressed its ideals by dressing in black, military surplus-style clothing and using a stage backdrop which amalgamated several "icons of authority" (including the Christian Cross, the swastika and the Union Flag) and an Ouroboros.
The band were critical of the punk movement itself, as well as wider youth culture in general. Crass promoted the type of anarcho-pacifism that eventually became more common in the punk music scene (see anarcho-punk). They are also considered part of the art punk genre, due to their use of tape collages, spoken word releases, poetry and improvisation.