Jean Dubuffet was a radical painter, printmaker and sculptor, determined to break down many of the barriers between high and low art in his search for the authentic or genuine. Dubuffet explored unusual materials in his innovative visual practice and tirelessly promoted art brut (outsider art). Highly influential as a writer on peripheral forms of art-making, Dubuffet generated considerable interest in untutored art practices hitherto considered repulsive, childlike, medically therapeutic or for prison inmates, opening up new fields of research into image production and eventually new markets—a development he would later parody. Yet for all his success and influence in the art world, he came to his artistic practice late in life—in his early 40s. Up until then he ran a wholesale wine business.

Regarding clumsy paint application, inaccurate draughtsmanship and muddy, disturbingly faecal-like textures—created by mixing oil paint with sand, tar and straw, and embedding detritus—as positive attributes, Dubuffet's ideas were very unusual, though often not entirely new. They grew out of his dislike of meticulous craftsmanship and refined intellectualism, an interest in children's art and a wish that his works look worn, scratched and battered. He despised the precious and exalted. He saw the unrestrained, raw, instinctive and violent as positive, valuable and oddly innocent. He was also attracted to the work of Dr Hans Prinzhorn, who studied the art of the mentally ill.

An inveterate exhibition-maker popular in North America and Europe, Dubuffet championed anti-bourgeoisie, anti-academy culture and non-professionalism with several styles, though he is best known for using red and blue, and compressed, organic, wobbly shapes on polystyrene. Later in his career he worked in fibreglass and resin in black and white. For most of his career, he concentrated on portraits of ordinary people, farm animals and mundane household objects.

From 1946 on, Dubuffet was represented by and showed regularly at the Pierre Matisse Gallery in New York, where he became unexpectedly popular and maintained a high profile. He was inspired by Algerian tribal art and made several trips to the Sahara.

Dubuffet presented acclaimed exhibitions at Musée des Arts Décoratifs, Paris (1960); The Museum of Modern Art, New York (1962); Art Institute of Chicago (1962); Palazzo Grassi, Venice (1964); Tate, London (1966); Stedelijk Museum, Amsterdam (1966); and Solomon R. Guggenheim Museum, New York (1966). A book of his writings, Prospectus et tous écrits suivants (Prospectus and all subsequent texts), was published in 1967. Retrospectives include: Museum Morsbroich, Leverkusen (1957); Akademie der Künste, Berlin (1980); Museum moderner Kunst, Vienna (1980); Josef Haubrich Kunsthalle, Cologne (1981); and Centre Pompidou, Paris (2001).