Prior has collaborated with many leading orchestras and ensembles, including The BBC Singers, the Royal Philharmonic Orchestra, the New Opera Orchestra, the Northern Sinfonia, and the ensemble Endymion. Highlights include a performance of his Sonata for Cello and Piano at the Moscow Tchaikovsky Conservatory and a symphonic poem, "Stalin's March", as part of the Arts Council-funded New Music Day with the City of London Sinfonia. Other performances include "The Prince's Feast" with Prior conducting the National Symphony Orchestra of London at the Barbican Centre and the premiere of "Svyatogor's Quest" by the Sitkovetsky Piano Trio at Wigmore Hall. In Autumn 2008, following performances in St. Petersburg, the Rossica Choir toured the UK, featuring Prior's choral cycle "Sounds of the Homeland" and parts of his "All Night Vigil".