The term Outsider Art origins from French art brut, whichwas created by the French artist Jean Dubuffet (1901-85).

In the mid-1940s, Dubuffet started collecting visual expressions created in a therapeutic context by, among others, psychiatric patients. He believed that these expressions had great artistic value – a bigger value than what was created in the academies of arts around Europe at the same time. He named these expressions art brut, which in direct translation means "raw art". Dubuffet considered these expressions to be: the gate to the pure and immaculate source of art because they were raw, spontaneous and not least untrained.

Dubufffet wrote in a memo about the works he sought to collect:

“We are looking for works of art that owe nothing to the imitation of works of art on display in museums. On the contrary, thy should draw upon the basic human experience and the most spontaneous personal invention. They should be creations produced from the creators own psyche, his own impulses and moods, without resorting to the standard accepted resources and without reference to current convention. Works of this kind interest us even if they are crude or clumsily executed”

In 1972, the British art critic Roger Cardinal wrote a book about art brut. The publisher wanted the book to have an English-sounding name. So art brut was translated into the English term Outsider Art. The concepts are today often used interchangeable.

In the1940s, Jean Dubuffet made quite strict requirements of what was to be defined as art brut. One of the criteria was for the artist to be unaffected by and isolated from, the surrounding society's traditions and trends, especially with respect to artistic expression.

The Outsider artists of our times are far more integrated in society and the socially isolated artists are fewer. The concept of Outsider Art is not as narrow in its meaning as the original art brut, which might be characterised as a historic concept.

Dubuffet and Cardinal both emphasise two conditions as being essential and characteristic of the term Outsider Art, which is, the biographic conditions relating to the creator of the artwork and the expression of the artwork as such.

The art scene has changed its nature since Dubuffet introduced the art brut concept. Almost anything is possible today - art can take on may forms: a landscape painting, a bunch of dead pigs, a virtual city, thoughts without physical shape etc. But even though the art scene in general has become more diversified in its expressions, there is still such thing as insider art – a sort of mainstream, canon or marked which the art or the artist is assessed and measured by.

Such canon is not defined by natural laws but is always a historically conditioned and thereby a changeable social construction, a commonly agreed trend or standard. Outsider Art is primarily created by people without great knowledge of and interest in the canon and trends, and this, among other things, is what gives Outsider Art its direct and innovative nature.

Jean Dubuffet had hoped that the recognition of art brut would shake the world of art. However, this head-on collision never took place. Rather, Outsider Art has today become a genre that asks important questions, gives us great experences and encourages discussions on art.