Collegium Musicum of London Chamber Choir was formed in 1972 by László Heltáy. He built an excellent reputation for the choir both in Britain and abroad, was its director until 1989, and retains his involvement as its President. With a regular pool of around 40 singers, the choir has a broad repertoire, having performed masses by Bach, Haydn, Mozart and Rossini as well as works by both early and contemporary composers.

Since 1997 the choir has been based at The Church of Our Most Holy Redeemer in Exmouth Market, though the ensemble has sung in a variety of venues from small parish churches to the Barbican, St James's, Piccadilly and St John’s Smith Square. It has appeared in a number of English festivals and, in 1990, gave a series of concerts of English music in Denmark. In July 1999, Collegium Musicum took part in the world première of Jonathan Dove's opera Tobias and the Angel in the Almeida Festival, and in 2000 the choir gave the first London performance in over 200 years of Benjamin Cooke’s A Christmas Ode. In 1997, under the direction of Peter Owens, the choir celebrated its 25th anniversary with a concert including Bernstein’s Chichester Psalms, Britten’s Rejoice in the Lamb and Janáček’s Otčenáš.

Works performed since 1998 have included Sir PeterMaxwell Davies’s Solstice of Light, music from The Fayrfax Manuscript, Monteverdi's 1610 Vespers, Rossini’s Petite Messe Solennelle, Handel’s Dixit Dominus, Britten’s Saint Nicolas, Mozart’s C minor Mass, Handel's Messiah, Vaughan Williams’s Flos Campi, Stravinsky's Mass, Purcell's King Arthur, Pizzetti's Requiem, Bach’s Magnificat, Orff’s Carmina Burana, as well as music by Bartók, Billings, Brahms, Bruckner, Byrd, Charpentier, Debussy, Dove, Dunstable, Dvořák, the Gabrielis, Gesualdo, Haydn, Holst, Howells, Ives, Mahler, Mendelssohn, Respighi, Scarlatti, Tallis, Vaughan Williams and Vivaldi. The choir specialises in singing music from Russia, having over the past seven years given four performances of Rachmaninov's All-night Vigil (Vespers), two performances of Rachmaninov's Liturgy of St John Chrysostom, and several concerts of music by other Russian composers. In 2001, the choir promoted a highly successful joint concert with the Moscow State University Academic Choir.

Collegium Musicum aims to present four programmes per year, with at least seven rehearsals in the six weeks preceeding each concert, as well as Christmas choral events.

Since July 2010, the choir has been led by BBC award-winning conductor Russell du Plessis, whose first concert - Monteverdi's 1610 Vespers - was a resounding success in October 2010.

above: CML performing Faire is the Heaven, English church music, Saturday, 10 October, 2009, Church of Our Most Holy Redeemer, Exmouth Market.