After the conclusion of the Kyrie (and Gloria), the celebrant kisses the altar and turns to greet the congregation:
v. Dominus vobiscum.
r. Et cum spiritu tuo.
v. The Lord be with you.
r. And with your spirit.
After the greeting of the congregation, the celebrant goes to the Missal and prays the Collect, the formal opening oration of the Mass (proper to the Mass).
At the conclusion the server and congregation respond with: Amen.