He lectures for the Royal Academy of Arts and the Oxford Lieder Festival and has written for The New Culture Forum, Literary Review, Eighteenth Century Music, Early Music, and Wagner. As a countertenor he recorded CDs of Gombert, Manchicourt, Crecquillon, and Clemens non Papa with The Brabant Ensemble.
Gulliver has also been assistant conductor with The National Orchestra of Lebanon, The National Orchestra of Malta, The Band of Instruments, and musical director for productions of Hansel and Gretel, Così fan tutte, Die Entführung, Il barbiere di Siviglia, Le nozze di Figaro, La Bohème and Eight Songs for a Mad King.
Gulliver works extensively with young voices. As Director of the three Hildegard Choirs, his recording of newly discovered works by Vaughan Williams and Liszt received glowing reviews from The Liszt Society and The Classical Review. He also directs the university choirs at Roehampton University and is director of the community choral society, The All Saints’ Singers. He gives frequent workshops for choirs and was invited by the Zimbabwe Academy of Music in Bulawayo to work with over 1600 children in Zimbabwe.
Gulliver has a love of cabaret and performs the songs of Gershwin, Noel Coward, Tom Lehrer, and Jacques Brel.