Chapter IV: The Different Forms of Celebration
74. In the local Church, first place should be given, because of its meaning, to the Mass at which the bishop presides surrounded by the college of presbyters and the minsters  and in which the people take full and active part. For this Mass is the preeminent expression of the Church.
75. Great importance should be attached to a Mass celebrated by any community, but especially by the parish community, inasmuch as it represents the universal Church gathered at a given time and place. This is particularly true of the community's celebration of the Lord's Day. 
76. Of those Masses celebrated by some communities, the conventual Mass, which is a part of the daily office, or the "community" Mass have particular significance. Although such Masses do not have a special form of celebration, it is most proper that they be celebrated with singing, with the full participation of all community members, whether religious or canons. In these Masses, therefore, individuals should exercise the function proper to the order or ministry they have received. All the priests who are not bound to celebrate individually for the pastoral benefit of the faithful should thus concelebrate at the conventual or community Mass, if possible. Further, all priests belonging to the community who are obliged to celebrate individually for the pastoral benefit of the faithful may also on the same day concelebrate at the conventual or community Mass.