She has been commissioned by the BBC, by festivals in UK and beyond, and by leading orchestras, ensembles and soloists.
Her catalogue includes a number of works for string ensemble, and chamber music for a wide variety of mediums, often including voice. She has a particular affinity for vocal music and has composed eight operas.
She is active in many aspects of the musical profession, as composer, teacher, director etc. From 1994–2008 she was Professor of Music at the University of York. Recent premieres include The Crimson Bird (2017, BBCSO/Ilan Volkov with Rachel Nicholls, soprano; text John Fuller), Triptych (2021,WCO/Anthony Hose with Jeremy Huw Williams, baritone; text Rowan Williams), Quintet for strings (2021, Sacconi quartet with Tim Lowe, cello) and several works for solo instruments, for voice and for chamber ensemble.
She was born in England in 1947: her mother was the composer Elizabeth Maconchy. LeFanu studied at Oxford, RCM and, as a Harkness Fellow, at Harvard. She is married to the Australian composer David Lumsdaine.