Glenville has sung more than ninety operatic roles, covering a wide range of styles from Cavalli to twenty-first century repertoire
During his later career, he specialised in the nineteenth century Italian roles, notably Rigoletto, Germont, Sharpless, Scarpia and Tonio. He made his debut at English National Opera in 1981 and at the Royal Opera House, Covent Garden the following year.
His career on the concert-platform has taken him from almost every major cathedral and concert-hall in the UK to venues throughout Europe and South America, singing all the standard repertoire from the Bach Passions to Carmina Burana and numerous contemporary works. He performed as a soloist with the Hallé Orchestra, National Orchestra of Spain, Northern Sinfonia, Royal Philharmonic Orchestra, Royal Liverpool Philharmonic Orchestra, Bournemouth Symphony Orchestra and the National Orchestra of Argentina. His recordings include Purgatory (Crosse), Caterina Cornaro (Donizetti) and many radio broadcasts, including The Creation, Elegy for Young Lovers, The Rake’s Progress, The Makropulos Case, War and Peace, Death in Venice, Carmina Burana and Friday Night is Music Night. He has worked with many distinguished conductors including Claudio Abbado, Oliver Dohnanyi, Carlo Rizzi, Richard Bonynge, Sir Mark Elder, Sir Charles Groves, Sir Richard Armstrong, Sir Alexander Gibson and Sir David Willcocks.
Throughout his performing career, Glenville has maintained a substantial teaching commitment. In 1986 he was appointed Senior Tutor in Vocal Studies at the Royal Northern College of Music and in 1997, he joined the Vocal Faculty at the Royal Academy of Music, where he has since held numerous posts, including Associate Director of Opera, Head of Opera Studies, LRAM Tutor and Senior Professor of Singing.
In addition to teaching singing, he lectures in Vocal Pedagogy and the Art of Teaching. Students, past and present, currently appear on the operatic stage and concert platform throughout the world and many have been the recipients of some of the most prestigious and lucrative singing awards (Wigmore Hall International Song Competition, Frederic Cox Prize, Miriam Lycette Scholarship, Richard Lewis Prize, Maggie Teyte Prize, Kathleen Ferrier Song Prize and Dame Eva Turner Scholarship), in addition to gaining places at the National Opera Studio and on young artists programmes at the Royal Opera House, Covent Garden and La Scala Opera House, Milan. In 2019, one of his mezzo-soprano students was a finalist in the Cardiff Singer of the World Competition.
Glenville has been a member of the Academic Board and the professorial representative on the Governing Body. He was awarded the status of Fellow of the Higher Education Academy in October 2011.