Alexander Calder at Botín Center by Hans Ulrich Obrist

Alexander Calder  (Lawnton, PA, 1898 – New York, NY, 1976) utilized his innovative genius to profoundly change the course of modern art. Born into a family of celebrated, though more classically trained artists, Calder developed a new method of sculpting: by bending and twisting wire, he essentially "drew" three-dimensional figures in space. He is renowned for the invention of the mobile, whose suspended, abstract elements move and balance in changing harmony. Coined by Marcel Duchamp in 1931, the word mobile refers to both “motion” and “motive” in French. Some of the earliest mobiles moved by a system of motors, although these mechanics were virtually abandoned as Calder developed mobiles that responded to air currents, light, humidity, and human interaction. He also created stationary abstract works that Jean Arp dubbed stabiles.

From the 1950s onward, Calder turned his attention to international commissions and increasingly devoted himself to making outdoor sculpture on a grand scale from bolted steel plate. Some of these major commissions include: .125, for the New York Port Authority in John F. Kennedy Airport (1957); Spirale, for UNESCO in Paris (1958); Teodelapio, for the city of Spoleto, Italy (1962); Trois disques, for the Expo in Montreal (1967); El Sol Rojo, for the Olympic Games in Mexico City (1968); La Grande vitesse, which was the first public art work to be funded by the National Endowment for the Arts (NEA), for the city of Grand Rapids, Michigan (1969); and Flamingo, for the General Services Administration in Chicago (1973).

Major retrospectives of Calder's work during his lifetime were held at the George Walter Vincent Smith Gallery, Springfield, Massachusetts (1938); The Museum of Modern Art, New York (1943–44); Solomon R. Guggenheim Museum, New York (1964–65); The Museum of Fine Arts, Houston (1964); Musée National d'Art Moderne, Paris (1965); Fondation Maeght, Saint-Paul-de-Vence, France (1969); and the Whitney Museum of American Art, New York (1976–77). Calder died in New York in 1976 at the age of seventy-eight.