Just as photography had introduced ideas of seriality and industrial processes into the practice of painting, the medium was similarly crucial in recasting the idea of sculpture in the 1960s and early 1970s. In place of the hard-edged geometries of Minimalism, artists such as Richard Serra, Robert Morris, and Lynda Benglis began working with a wider array of malleable materials, from molten lead and neon to felt and dirt—substances that retained traces of the artist’s forming gestures and clung to or sullied the space that they occupied, in opposition to Minimalism’s smooth, ordered forms. Others similarly trained in Minimalism tried to liberate sculpture from the gallery and museum altogether, making works that were inextricably bound to their site. Like Serra and Bruce Nauman, earthwork artists such as Robert Smithson, Dennis Oppenheim, and Michael Heizer were also fascinated by process and gesture, but installed their works in ravaged industrial sites and far-flung corners of the world, creating pieces that were largely dependent upon photography as witness to their existence; the most famous earthwork is Smithson’s Spiral Jetty (1970)—a 1,500-foot sculpture made of mud, salt crystals, and rock coiling over ten acres of the Great Salt Lake in Utah.

At the same time that some sculptors turned outward toward the wider landscape, others turned in upon their own bodies as both the subject and object of sculptural activity. One work that brilliantly moved in both directions simultaneously was Richard Long’s A Line Made by Walking from 1967, in which the artist repeatedly trod across a field in the English countryside to form a temporary imprint in the earth that was given longer life in the act of photographic documentation. Between 1966 and 1968, Nauman retreated to the studio to make a landmark series of films, videos, and photographs in which he performed complex series of movements or activities such as keeping two balls bouncing simultaneously over long periods of time, juxtaposing the clarity and simplicity of the conceptual directive with the body’s attempts to keep pace.

Vito Acconci moved from the practice of poetry into video, performance, and photography not simply to document an ephemeral event but within a systematic exploration of his body’s “occupancy” of public space (the street, theater proscenium) through the execution of preconceived actions or activities. Acconci created his perhaps best-known work over the course of three weeks in October 1969, during which time he followed a stranger until that person entered a private space; the artist recorded these pursuits in photographs (made by a third party) and a written log. By keying his own movements to the perambulations of randomly chosen pedestrians, Acconci attempted to reconceive the role of the artist as a keenly attentive mirror to the world; as the artist described it, “I am almost not an ‘I’ anymore; I put myself in the service of [the] scheme.”