Geoffrey Hendricks was a visual artist associated with the Fluxus movement. The leaders of an international, interdisciplinary movement of artists, composers, designers, and poets during the 1960s and 1970s, members of Fluxus engaged in experimental art practices and Happenings, with a shared emphasis on process over product. Hendricks was nicknamed "Cloudsmith” by fellow Fluxus artist Dick Higgins, in reference to his expansive multimedia body of work depicting cloud-filled skies in paintings, on objects, in installations, and in performances.

This body of work ultimately culminated in a retrospective exhibition More than 100 Skies at the Fondation du Doute in Blois, France, in 2017. Hendricks is also remembered for his Headstand performances, executed between 1994 and 2012. These radically minimalist performances engaged the smallest fixed space the artist’s body could occupy. For their duration, Hendricks posed standing on his head, for extended periods of time, often painted blue or with sculptural elements or signage dangling from his feet.

Hendricks’ work has been included in exhibitions at the Whitney Museum of American Art, New York and the Museum of Modern Art, New York among others. He was Professor Emeritus of Art at the Mason Gross School of the Arts at Rutgers University, where he taught from 1956 until his retirement in 2003.