Gary Milton Smith was born on 15 March 1943, in Payette, Idaho to Milton F. and Lillian Raby Smith. He attended Idaho State University and Utah State University. He graduated from Utah State University in 1967 and began graduate school the following year where he pursued his degree in Outdoor Recreation, specializing in Environmental Public Affairs. His thesis involved the production of a slide and film promotion presentation on the Mt. Naomi Wilderness Area. In the summer during his university education, as well as after his graduation, Gary worked as a forest ranger, naturalist, and various other positions in national forests and parks.

On 4 July 1969, Gary Milton Smith married Lillian Francuz in Idaho Falls, Idaho. That same year he joined the Marine Corps where he attained the rank of captain. Gary remained on active duty until 1972. As a Marine, Gary served in Quantico, Virginia where he worked as the Associate Editor of the Marine Corps Gazette, was the Special Projects Officer at the Basic School, and designed an exhibit on the Basic School and combat photography. He also served as the Public Affairs Officer in Okinawa, Japan. He graduated from the Department of Informational Defense School in 1970. In 1972, Gary received a Presidential Commendation for outstanding military service.

One of Gary Smith's occupations was as a song writer. He wrote music and lyrics for songs which he used in his jobs with the National Forest Service and his work as an environmentalist. In 1975, Gary published a book about his songs entitled Windsinger. One of his songs, "Dick's Song," was used by CBS in a 60-Minutes program concerning Lake Powell. Gary along with Robert Redford and representative of the Environmental Defense Fund took part in his program.

In 1975, Gary stopped his graduate school training after he was diagnosed with Multiple Sclerosis. He continued, however, writing articles for magazines and newspapers on environmental and social issues. He became active in the Multiple Sclerosis Society, playing benefit concerts on behalf of the organization. In 1979, the National Multiple Sclerosis Society awarded Gary Smith the Patient Achievement Award for his region. Gary also served on the Commission for Persons with Disabilities for the Catholic Diocese of Salt Lake City, Utah. In 1980, he was recognized as Conservationist of the Year by the Bridgerland Audubon Society, and in 1984, he was given the Bridger Award for Outstanding Service to Conservation by the Natural Resources Department at Utah State University.

In 1981, Gary Smith went back to graduate school and received his Master's of Science in Recreational Resource Management in 1984. His thesis was entitled, "The Mystery Song: A Walk with Masawe." That year he and Lillian divorced. Four years later, on 7 April 1988, Gary Milton Smith died. He was buried in Mt. Moriah Cemetery in Pocatello, Idaho.