Gary Duncan is an American guitarist and songwriter, best known as a founding member of the psychedelic rock band Quicksilver Messenger Service, formed in San Francisco in 1965. His primary genre includes psychedelic rock, blues rock, and folk rock. Duncan's distinctive guitar work and improvisational style contributed significantly to the band's sound, characterized by intricate harmonies and extended jam sessions. Notable works include Quicksilver Messenger Service's self-titled debut album (1968), which features the classic track "Fresh Air," and the critically acclaimed "Happy Trails" (1969), a live album that showcases the band's dynamic performances. Duncan also had a hand in writing and co-writing several songs, including "What About Me," which became a hit for the band. Duncan's influence on music extends beyond Quicksilver, as he helped shape the San Francisco sound of the 1960s, inspiring many subsequent musicians in the realms of rock and improvisational music. His innovative approach and contributions to the genre solidified his legacy as an important figure in the evolution of American rock music. Duncan continued to perform and record throughout his life, maintaining a connection to his musical roots until his passing in 2023.