Londinium is a dynamic London-based chamber choir which particularly specialises in the performance of unusual a cappella repertoire, ranging from the Renaissance to the 21st century. The choir's Musical Director is Andrew Griffiths. Since its debut in November 2005, this versatile group has been noted for its 'fine line and clear sound' and 'lovely transparency of texture' (Robert Hugill, Music and Vision) and its innovative programming of rarely performed works, such as Palestrina's Missa Tu es Petrus, Liszt's Missa Choralis, Schoenberg's Friede auf Erden and, most recently, Mäntyjärvi's Canticum Calamitatis Maritimae, Vasks' Māte Saule and Pizzetti's Requiem.
Londinium has been praised for its performances of contemporary repertoire. Composer Cecilia McDowall found the choir's sound "just gorgeous – both luscious and true" in a programme which included her setting of Regina Caeli (May 2009), and Eric Whitacre commended Londinium for "One of the most beautiful performances of Sleep I have ever heard" (November 2010).
In May 2010 Londinium featured in the Classical Brit Awards at the Royal Albert Hall as the chorus in live performances by Bryn Terfel and Rolando Villazón. The ensemble has performed at the British Library and Cliveden House, and for Special Olympics Great Britain. In May 2011 Londinium provided the music at a gala dinner for the David Shepherd Wildlife Foundation to celebrate the artist's 80th birthday.
On 4 June 2011 Londinium gave the World Première of Perpetual Light: Requiem for an Unscorched Earth, by Jessica Curry, conducted by Andrew Griffiths at the Old Vic Tunnels: 'a dark, tormented piece, punctuated by moments of brightness...that radiated hope, the emotional thread that tied the whole piece together. From start to finish, Londinium perfectly captured this delicate emotion...' (Kay Kempin Bachtrack).