The singing of acclamations is most important in fostering people's active participation in the liturgy. Singing of the dialogues between the minister and the people is also strongly encuraged, as such singing helps express the unity of the assembly, particularly large assemblies.
The Gospel and Eucharistic prayer acclamations are the highest priorities for the people's singing, more important than any other songs of the liturgy.
Even when nothing else is sung, the Alleluia, Sanctus, Memorial Acclamation and Amen at the end of the Eucharistic prayer should be sung by all in every Mass, even unaccompanied.
