Allan Kaprow’s death this spring at age seventy-eight, a profound loss by any measure, is all the more impropitious given the recent upsurge of interest in his work and the growing awareness of his contemporary relevance. While his happenings gained widespread notoriety in artistic circles and mass culture alike during the ’60s and ’70s, his evolving critical writings and activities both then and in later years resonate strongly within the context of today’s vital considerations of performance and spectatorship, aesthetics and politics, and private experience in an age of spectacularized commerce. Taking pause to reflect on Kaprow’s legacy, Artforum asked art historians Judith Rodenbeck and Jeff Kelley, as well as artists Lucas Samaras, Suzanne Lacy, and Paul McCarthy, to look again at the “un-art” and life of this pivotal figure. Those contributions are included here, along with a special, web-only reminiscence from Yoko Ono.