Brett Dean (born 23 October 1961) is an Australian composer, violist and conductor.
 Brett Dean was born, raised, and educated in Brisbane. He attended Brisbane State High School.
 He started learning violin at age 8, and later studied viola with Elizabeth Morgan and John Curro at the Queensland Conservatorium, where he graduated in 1982 with the Conservatorium Medal for the highest-achieving student of the year. In 1981 he was a prizewinner in the ABC Symphony Australia Young Performers Awards. 
 From 1985 to 1999, Dean was a violist in the Berlin Philharmonic Orchestra. In 2000, he decided to pursue a freelance career and returned to Australia, where his many appointments have included curating classical music programs with the Sydney Festival (2005) and the Melbourne Festival (2009). As a composer and musician, he is a regularly invited guest to concert stages around the world. He was the composer-in-residence for the Taiwanese National Symphony Orchestra's 2016/17 season and the Creative Chair for the Tonhalle-Orchester Zürich's 2017/2018 season.
 Dean was artistic director of the Australian National Academy of Music in Melbourne until June 2010, when his brother, Paul, took up the post.
 The Melbourne Symphony Orchestra celebrated Dean's 50th birthday, and his contribution to music as composer, performer and teacher, in its 2011 Metropolis Festival.
 He is married to Australian visual artist Heather Betts, and his daughter is the Australian mezzo-soprano Lotte Betts-Dean.
 Dean began composing in 1988, initially focusing on experimental film and radio projects as well as improvisational performance. Since then, he has created numerous compositions, mainly orchestral or chamber music as well as concertos for several solo instruments. His most successful work is Carlo for strings, sample and tape, inspired by the music of Carlo Gesualdo. On 7 September 2008 his work Polysomnography for wind quintet and piano received its world premiere at the Lucerne Festival; on 2 October 2008 Simon Rattle conducted the first performance of the orchestral song cycle Songs of Joy in Philadelphia. His first opera, Bliss, based on the novel by Peter Carey, premiered at Opera Australia in 2010.
 Dean's compositional style is known for creating dynamic soundscapes and treating single instrumental parts with complex rhythms. He shapes musical extremes, from harsh explosions to inaudibility. Modern playing techniques are as characteristic for his style as an elaborate percussion scoring, often enriched with objects from everyday life. Much of Dean's work draws from literary, political or visual stimuli, transporting a non-musical message. Environmental problems are the subject of Water Music and Pastoral Symphony, while Vexations and Devotions deal with the absurdities of a modern society obsessed with information.
 In April 2013, "The Last Days of Socrates" was premiered by the Berlin Philharmonic. The work for bass-baritone, choir, and orchestra was a co-commission of the Rundfunkchor Berlin, the Los Angeles Philharmonic and the Melbourne Symphony Orchestra.
 In August 2014, "Electric Prelude" was premiered during the BBC Proms 2014 and was conducted by Sakari Oramo.
 Dean's clarinet concerto Ariel's Music won an award from the UNESCO International Rostrum of Composers in 1995. Winter Songs for tenor and wind quintet received the Paul Lowin Song Cycle Prize in 2001; Moments of Bliss for orchestra was named Best Composition at the Australian Classical Music Awards in 2005. In 2002–03, Dean was artist-in-residence with the Melbourne Symphony Orchestra and composer-in-residence at the Cheltenham Festival. In 2007–08, he became artist-in-residence with the Radio-Sinfonieorchester Stuttgart des SWR.
 Dean was awarded an honorary doctorate from Griffith University in Brisbane on 21 June 2007. On 1 December 2008, he was awarded the 2009 University of Louisville Grawemeyer Award for Music Composition for his violin concerto, The Lost Art of Letter Writing. In September 2011, he was composer-in-residence at the Trondheim Chamber Music Festival.
 Dean received two Ivor Novello Award nominations at The Ivors Classical Awards 2023. Cello Concerto and In This Brief Moment were both nominated for Best Orchestral Composition. The Cello Concerto won the award.
 The APRA Awards are presented annually since 1982 by the Australasian Performing Right Association (APRA).
 The ARIA Music Awards is an annual awards ceremony that recognises excellence, innovation, and achievement across all genres of Australian music. They commenced in 1987. 

 The Sir Bernard Heinze Memorial Award is given to a person who has made an outstanding contribution to music in Australia.
 The Don Banks Music Award was established in 1984 to publicly honour a senior artist of high distinction who has made an outstanding and sustained contribution to music in Australia. It was founded by the Australia Council in honour of Don Banks, Australian composer, performer and the first chair of its music board.
 The Helpmann Awards is an awards show, celebrating live entertainment and performing arts in Australia, presented by industry group Live Performance Australia since 2001. Note: 2020 and 2021 were cancelled due to the COVID-19 pandemic.