Along with Fluxus, the Happening is one of the most important forms of action art of the 1960s. A happening is an event improvised directly with the audience. One of the early forms of happening is the dé-coll/age happening. This includes throwing objects into the audience, exhibitionism, orgies of blood and paint, destroying, tearing, spoiling objects. The aim is to create a shock effect on an audience that is involved in the event through a wide variety of actions. The audience is part of the action conceived by the artist. The audience is included in the artistic actions, whereby the course of events is not fixed from the outset. Depending on the reaction of the audience, improvisation can vary (although happenings are seldom completely improvised, but rather rehearsed in advance). This also means that happenings usually do not have a fixed time frame; often the audience does not even know when the happening is over. Another characteristic of the happening is the use of different objects and their random or deliberate juxtaposition, which is also a basic principle of surrealism.
The term was first used by Allan Kaprow in 1959 for an action at the Reuben Gallery in New York, which consisted of 18 happenings in six parts. There were three rooms, separated from each other by plastic sheeting, in which the events took place at the same time. However, Kaprow had already used the term in his essay "The Legacy of Jackson Pollock", published in 1958, where he sketched out a prognosis for the art of the post-Pollock generation.
The aim of the Happening artists was to expand the traditional concept of art and to connect art with everyday life. In doing so, everyday actions were to be made clear to people and thereby abstracted. The boundary between Fluxus and Happening cannot be defined exactly, as some artists orientate themselves towards and participate in both forms of action.