The Agnus Dei, an acclamation addressed to Christ, the Lamb of God, forms part of the Ordinary of the Mass - that is, a part of the Mass that does not change except for slight modifications for the Requiem Mass. As a relatively unchanging, repeated element in the liturgy, it has been a necessary part of musical settings, whether as plainchant or in the varying styles of later generations. This CD features 11 different versions, plus six other liturgical works.