“Happening: Happenings developed from a combination of assemblage and environment art as artists sought to free art further from the constraints of the wall and the frame. Resembling performance, these events often involved sculpture, sound, time, motion, and living persons. While participants began with a plan, there was no rehearsal and no repeat performance. Spontaneous audience participation was sometimes encouraged. Allen Kaprow is credited with inventing happenings, which took place in New York City in the 1960s.”
Excerpted from: Diamond, David G. The Bulfinch Pocket Dictionary of Art Terms. Boston: Little Brown, 1992.