Dean studied at the Queensland Conservatorium where he received a Medal of Excellence. In 1981 he was a prize winner 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 career as a freelance artist and returned to Australia. As a composer and musician, he is a regularly invited guest to many professional concert stages around the world. Brett Dean was Artistic Director of the Australian National Academy of Music in Melbourne until June 2010 when his brother, Paul Dean, took up the post.
The Melbourne Symphony Orchestra celebrated Brett Dean's 50th birthday, and his contribution to music as composer, performer and teacher, in its 2011 Metropolis Festival.