Derek Bourgeois was born in Kingston upon Thames in 1941. After receiving his university education at Magdalene College, Cambridge (honours degree and doctorate), Bourgeois spent two years at the Royal College of Music, studying composition with Herbert Howells and conducting with Sir Adrian Boult.
From 1971 to 1984, Bourgeois was a lecturer in music at Bristol University, and director of the National Youth Orchestra from 1984 to 1993. In 1980 he began conducting the Sun Life Band (now the Stanshawe Band of Bristol), which was his introduction to brass bands. In 1994 Bourgeois was appointed Director of Music at St Paul's Girls School, London, a position previously held by a number of noted composers, including Gustav Holst and Herbert Howells.
After retiring from this post in 2002 he and his wife settled in Mallorca. Following her death in 2006, he remarried in 2008 and moved to New York City, but returned to the United Kingdom in 2009. He has also conducted for various orchestras. His symphonies include Jabbervocky-Extravaganza (1963) and the symphonic fantasy The Astronauts (1969). For his Symphony of Winds, the First International Conference for Conductors, Publishers and Composers awarded him with their main commission in 1981. He has also chaired Composer's Guild of Great Britain and served as the artistic director of Bristol Philharmonic Orchestra. He founded the National Youth Chamber Orchestra of Great Britain in 1988. He has also been a member of the Music Advisory Panel of the Arts Council.
Bourgeois has been a prolific composer for brass bands and wind bands. His works in that area include two Concerti for Brass Band, the Concerto Grosso, Blitz, Diversions, Serenade, The Devil and the Deep Blue Sea, and Apocalypse. Reviewing Bourgeois' Sonata for Trombone, David Vinning of Trombone.org wrote: "Bourgeois is a skilled composer who knows how to write for the trombone and this piece is a major new work sure to become popular." Bourgeois' first band work was a concerto, adapted from a flute concerto. He has also played the tuba.
Bourgeois' first symphony, which he composed at the age of 18, was positively reviewed in The Guardian by Stanley Sadie, the future editor of Grove's Dictionary. By 2009, Bourgeois had written 44 symphonies, well beyond the number composed by Havergal Brian, and a larger number than were produced by most 19th and 20th century composers. In an interview with Alan Rusbridger of The Guardian, he said that the symphonies came "tumbling out." By 2017 he had 114 symphonies to his name.
Bourgeois has also composed music for the television movie The Crucible, the short documentaries Thirty Million Letters (1963) and The Driving Force (1966), the TV series The Barchester Chronicles, Mansfield Park (1983), and the "Buddyboy" episode of the TV series Beasts.
His first wife, the violinist Jean Bourgeois, died of motor neuron disease on 27 November 2006. She had played in the BBC National Orchestra of Wales and was also a piano teacher. Since returning to the UK from the USA in 2009, Bourgeois lived Wool, Dorset, with his second wife, Norma Bourgeois. He died on 6 September 2017 in Poole, Dorset, with his wife Norma by his side.