Over the last 40 years, Robert Glenn Ketchum's imagery, writing, exhibitions, numerous books and personal activism have helped to define photography's successful use in conservation advocacy. At the same time, Ketchum's decades of color printing are one of the most unique bodies of work in contemporary color photography, and the textile translations of his photographs created in China since the early 1980's are among the most beautiful and complex textiles in contemporary art.

Ketchum was named by Audubon magazine as one of the 100 people "who shaped the environmental movement of the 20th Century." American Photo magazine listed him one of the 100 most important people in contemporary photography in the 1990's, and then in 2010, named him 5th in their very select American Masters series. Henri Cartier-Bresson, Richard Avedon, Helmut Newton, and Annie Leibovitz, were the four previously recognized. Recent work in new technologies has further prompted Digital Photo Pro magazine to name Ketchum one of the new digital masters.

Ketchum's work is in numerous collections including the Museum of Modern Art, New York; Metropolitan Museum of Art, New York; Los Angeles County Museum of Art; High Museum of Art, Atlanta, Georgia; and the Houston Museum of Fine Art, Texas. Large study collections have been established at the Huntington Library, Art Collections, and Botanical Gardens, San Marino, CA; and the Amon Carter Museum, Fort Worth, Texas.

Ketchum received his B.A. cum laude from UCLA, where he studied with Robert Heinecken, Edmund Teske and Robert Fichter. Ketchum was one of the first MFA's from California Institute of the Arts, where he also taught briefly, and he has also received an honorary MS from Brooks Institute of Photography.

Ketchum was a founding board member of the Los Angeles Center for Photographic Studies. As a curator he discovered, developed and toured the historic archive of the seminal color photographer, Paul Outerbridge; assembled a life retrospective of eminent black photographer, James Van der Zee; and, was the first to show notable contemporary color photographer John Divola's "Zuma" series. For 15-years, Ketchum also served as served as the Curator of Photography for the National Park Foundation for whom he organized the exhibit and wrote American Photographers and the National Parks, the defining history of conservation photography in North America.

Ketchum is a founding Fellow of the International League of Conservation Photographers (ILCP), and a lifetime Trustee of the Alaska Conservation Foundation. He is also a distinguished lecturer and teacher whose public engagements have included everything from small high schools to large colleges, multi-national corporations and the National Academy of Sciences. In 2015 Ketchum was given the Explorer's Club's Lowell Thomas Award in recognition for his decades-long efforts to bring environmental conservation to the world's attention. In 2020 the Booth Western Art Museum in Cartersville, Georgia, displayed Ketchum's second largest museum exhibition of his career.

In 1992, Ketchum was the first artist to be admitted as a Resident Artist Member at the Jonathan Club.