This year's theme is "Enlightenment". Each of the participating choirs brings a piece of music to the event, resulting in an eclectic and exuberant festival of music in varied styles and sound-worlds. But they combine their forces in a performance of a larger work, and for this Canterbury event they will perform four movements from Monteverdi's spectacular Vespers of 1610.

At the start and end of each half of the concert, these four pieces - originally written for St Mark's Basilica in Venice - will create a sublime frame for the individual offerings. The final movement is the Magnificat: an astonishing display of compositional virtuosity, treating a simple plainsong melody to the brilliantly colourful resources of voices and instruments, making full use of the wonderful spaces and acoustics of the Cathedral Nave.