As a student at Kingston University Symon Clarke composed music for string orchestra, two string quartets for the Medici String Quartet and a large-scale orchestral work to a commission from the Stoneleigh Youth Orchestra entitled The Place of the Solitaires which was performed to critical acclaim at the Fairfield Halls, Croydon in 1980.

He won first prize in the Greater London Arts Association’s Young Composers Competition in 1981 with a piece for clarinet and piano. 
The success of these works led to further commissions and performances, for example, Ouvrage en Mosaïque for solo piano (Andrew Ball), Perihelion for Lontano, Cepheid Variables for Divertimenti, Metoikos for the Gabrielli Brass Ensemble (featuring soloists Mary King and Jane Manning) and String Quartet No 1 for the Brindisi String Quartet.

His music has been broadcast in Music of our Time, Hear and Now, Late Junction and World Music Week on Radio 3 and elsewhere in Europe and Asia.