In 1926 she began studying at the Royal College of Music, London, where she was taught by Gordon Jacob and Ralph Vaughan Williams.

[2] During the Second World War, the students were evacuated to Grantham in Lincolnshire, where she composed some of her earliest works, including the Sinfonia Concertante for piano and orchestra, and her First Symphony.

[4] Ballads for Orchestra of 1968, written for the National Eisteddfod, held that year in her home town, has all the colour and swagger of a mediaeval court.

Outstanding amongst her vocal works are her setting of the Latin hymn, Ave Maris Stella, for unaccompanied SATB (1973), and Six Poems by Gerard Manley Hopkins, for contralto and string sextet (1958).

The cycle is book-ended by two of Hopkins' best-known poems, Pied Beauty and Windhover, her music perfectly matching the rhythmic subtlety of the texts.

Welsh-language settings include Saunders Lewis's carol Rhosyn Duw, for SATB, piano and viola (1955), which she later incorporated into her large-scale choral work, Missa Cambrensis (1971).

The Symphony No 1 (1943) was performed by the BBC National Orchestra of Wales conducted by Owain Arwel Hughes in a 3 March 2008 broadcast.

[14][15] Also in 2024 an album of 29 of her songs was released in premiere recordings, including Stand forth, Seithenin, Fairground and her setting of Lights Out by Edward Thomas.

[20] March 2016 saw both the premiere modern performances of her large-scale Missa Cambrensis for soloists, chorus and orchestra (1971) and of her symphonic suite Four Illustrations for the Legend of Rhiannon (1939–40).