[3] She studied with John Tavener while at the North London Collegiate School[4] and subsequently with Robin Holloway at King's College, Cambridge, graduating in 1976.
[3] Before going to Cambridge Weir had a six-month period at the Massachusetts Institute of Technology learning about computer music and acoustics.
[3] Her work Campanile "in which a concertino core derived from Bach's Nun ist das Heil is framed by two Brahmsian elegies" won the first prize in the International Festival of Youth Orchestras in Aberdeen in 1974 where the jury included Aaron Copland.
[3] She won a Koussevitzky fellowship the following summer resulting in several compositions including what "she consider[ed] her true opus 1", Out of the Air.
[6] Her first stage work, The Black Spider, is a one-act opera that was premiered in Canterbury in 1985, loosely based on the short novel of the same name by Jeremias Gotthelf.
On 30 June 2014, The Guardian stated that her appointment as Master of the Queen's Music,[10] succeeding Sir Peter Maxwell Davies (whose term of office expired in March 2014), would be announced;[11] this was officially confirmed on 21 July.
She was commissioned to compose an a cappella work for the state funeral of Elizabeth II on 19 September 2022, and wrote a setting of Psalm 42, "Like as the hart".
[18] Weir was appointed Commander of the Order of the British Empire (CBE) in the 1995 Birthday Honours for services to music.
[22] She was promoted Dame Commander of the Order of the British Empire (DBE) in the 2024 New Year Honours for services to music.