When Lithuanian-born sculptor Jacques Lipchitz emigrated to Paris in 1909, his friendship with the Spanish artists Juan Gris and Pablo Picasso led him to explore Cubism in his sculptures. By the late 1920s, however, Lipchitz moved from these figures made of flat planes and angular masses to a looser style based on natural forms, and he began to explore themes and ideas in his sculptures rather than purely formal relationships. The theme of Prometheus emerged as early as 1933 in his work, as a symbol of human progress and determination and a parable for the triumph of democracy over fascism. In the Greek legend, Prometheus stole fire from the gods and bestowed it as a gift on humankind. This so enraged the god Zeus that he had Prometheus chained to a rocky mountainside, to be tortured by a vulture for all eternity. In Lipchitz's sculptural version of the story, however, Prometheus triumphs over his fate: freed from his chains, he strangles the bird with one hand as he grips the claws in the other. The original version of Prometheus Strangling the Vulture was a 30-foot work cast in plaster for the 1937 International Exhibition in Paris. After the artist resettled in America, the Brazilian government commissioned him to sculpt another Prometheus for the Ministry of Education and Health building in Rio de Janeiro. The Walker sculpture is based on this 1944 version, which was recast in bronze in 1953.

In the years after World War II, Isamu Noguchi designed stage sets and costumes for the most advanced choreographers of the day: Martha Graham, Merce Cunningham, and George Balanchine. This sculpture was originally an element of the stage design for Graham's 1950 Judith, a dramatization in dance of the Old Testament story in which the Hebrew widow saves Jerusalem by seducing the dreaded invader Holofernes and beheading him in his own bed. The structure in the Garden--originally made of balsa wood and recast by Noguchi in bronze nearly thirty years later--was covered with one of Graham's signature flowing cloths to form a tent at the moment of the dramatic deed. The fragile balance of the sculpture's four skeletal, weaponlike elements imparts the tense excitement of the story's dangerous scheme and recalls other of the artist's gravity-defying sculptures of the period. His 1947 pieces Avatar and Cronos, also in the Walker's permanent collection, are similar assemblages of slender elements joined together in an intricate system of balance.

Henry Moore once titled this standing figure Winged Victory. With her truncated arms and neck and elongated, protruding torso, she indeed recalls the famed Greek figure of that name. But the real inspiration for this creature was the breastbone of a bird. Moore discovered principles of form and rhythm for his sculptures in a variety of natural objects, such as rocks and plants. He had a particular fascination with bones and collected, studied, and drew them extensively to explore their complexity and dynamism. He incorporated the actual bird bone into an early maquette for this sculpture, eventually infusing its "knife-edge thinness" throughout the entire figure and retaining the rough, porous texture of bone in the work's bronze surface. Viewed from differing perspectives, the sculpture appears alternately razor sharp or rhythmically curvaceous.

More than 26 feet high and 42 feet wide, and weighing in at approximately three tons, Mark di Suvero's Arikidea is certainly deserving of the description "monumental." Yet this massive structure belies an ingeniously constructed delicacy. The gigantic steel beams have been masterfully balanced in such a way that a simple touch or a passing breeze will cause the structure to sway gently. The wooden swing suspended from its center playfully invites the viewer to further interact with the work, moving into and through its airy spaces. Beginning in the late 1950s, di Suvero drew on the gestural ideas of Abstract Expressionist painting, extending them into the three-dimensional realm of sculpture. His early cantilevered constructions of junkyard detritus (old tires, scrap metal, steel girders) later gave way to the massive, outdoor steel sculptures for which he is known today. The title of this piece evolved loosely from the word arachnid, Greek for "spider," a creature di Suvero admired for its capacity to create structures in space.