Colin’s career encompasses performing, teaching, writing and directing. As a singer, he is known principally as a character baritone, having worked for many years with companies such as Garsington Opera, Opera Restor'd, The New Savoyards, Opera Interludes, Country Opera etc. Such roles have included Sempronio (Lo Speziale), Don Alfonso (Cosi fan Tutte), Geronimo (Il Matrimonio Segreto), Bartolo (Il Barbiere di Siviglia), Sorceress (Dido and Aeneas) to name but a few. In addition, Colin has performed much contemporary music with groups such as the London Sinfonietta, Phoenix and New Chamber Opera. One of Colin’s signature roles is the soloist in Maxwell Davies' Eight Songs for a Mad King, a role he has previously performed with various groups in the UK and Europe. On the concert platform, he has appeared with the  Britten Sinfonia, the Ochestra of the Age of Enlightenment, The Southern Camerata (under David Hill), L’Orchestra National de Picardie and L’Orchestra National de Lille, to mention just a few.

Colin has sung frequently on BBC Radios Two and Three, and has made several CDs; most recently appearing as Bass soloist in Bach's St John Passion (Naxos). In recent years, he has also enjoyed considerable success as a cabaret artist, performing the songs of Noël Coward and contemporaries.

As a teacher, Colin has had a long association with the University of Oxford, having been, for many years, the singing teacher at New College. Now, however, he splits his teaching between London and Umbria. He receives frequent invitations to teach around the world, and is a visiting professor at Utah State University (USA), and on the Cisternino choral course, Italy. He is also director of the Scheggino Advanced Course for Singers in Umbria.

Colin has directed productions of Cosi fan tutte (two productions), Le nozze di Figaro, Il Seraglio, Trial by Jury (three productions), Il barbiere di Siviglia, L'elisir d'amore, The old maid and the thief, L'enfant et les sortileges, Riders to the Sea, Dido and Aeneas and Venus and Adonis. He is Artistic Director of Hand Made Opera, which he co-founded in 2000.

In 2002, Colin published a book on vocal technique for the RSCM (Voice for Life, 5) and has also been published by The Guardian, Church Music Quarterly and The Independent. His latest book, The Student Voice, aimed at anyone who is serious about working on their voice, is published by Dunedin Academic Press in September 2008