Seán’s choral works have received many international performances and have garnered numerous awards: he has won the Feis Ceoil choral composition award four times (2009, 2011, 2014, 2016), the Choir and Organ Magazine composition competition twice (2012, 2014), the St Giles’s Cathedral Edinburgh anthem composition competition, the Fragments Choral Composition Award (in association with Historic Scotland), and the Prix pour une œuvre de création at the international choral festival Florilège Vocal de Tours, France. His choral works have been performed by choirs including the choir of Merton College, Oxford, the choir of Salisbury Cathedral, the National Youth Choir of Scotland, the choir of St Giles’ Cathedral, Edinburgh, Chicago a cappella, the Grant Park Chorus, Chicago, Laetare Vocal Ensemble, Voci nuove, the Mornington Singers, and New Dublin Voices.

Seán has also written much chamber music: he has twice been awarded the Young Composers’ Bursary at the West Cork Chamber Music Festival (2013, 2014), the Jerome Hynes composition competition (2011), was a finalist in the BBC Radio 3 / National Centre for Early Music’s Composers’ Award 2013. He was commissioned by the Vanbrugh Quartet to compose his String Quartet No. 3, ‘The Devil’s Dream’ for their Crossings Project, by the West Cork Chamber Music Festival to composeLament for the Poets 1916 for the Vanbrugh Quartet and soprano Caroline Melzer, and by the EstOvest Festival to compose No Go for Xenia Ensemble and uilleann piper Eoin O’Riabhaigh.