"One of the ministries adapted to present day needs in the Latin Church, otherwise known as reader. The Lector is appointed to read the word of God in the liturgical assembly. Accordingly he or she reads the lesson from Sacred Scripture, except the Gospel, in the Mass and in other sacred celebrations; recites the psalms between the readings in absence of the psalmist; presents the intentions for general intercessions when the deacon or cantor is absent; and may also direct the congregation in the singing. If necessary he or she also assumes the responsibility of instructing any of the faithful called upon to read the Scriptures in any liturgical
celebration.
Cantor
The chief singer of an ecclesiastical choir, who leads the singing. In the Divine Office the cantor intones the antiphons and starts the psalms. The Cantor is also called the precentor.
Extraordinary Minister of Holy Communion
In every celebration of the Eucharist, there should be a sufficient number of ministers of Holy Communion so that it may be distributed in a reverent and orderly manner. Bishops, priests and deacons distribute Holy Communion in virtue of their office as ordinary ministers of the Body and Blood of the Lord. (1) When the size of the congregation or the incapacity of the bishop, priest, or deacon requires it, the celebrant may be assisted by other bishops, priests, or deacons. If such ordinary ministers of Holy Communion are not present, "the priest may call upon extraordinary ministers to assist him, i.e., duly instituted acolytes or even other faithful who have been deputed for this purpose. In case of necessity, the priest may also depute suitable faithful for this single occasion (GIRM 162)."
Extraordinary Ministers of Holy Communion should receive sufficient spiritual, theological, and practical preparation to fulfill their role with knowledge and reverence. In all matters they should follow the guidance of the diocesan bishop ( Norms for the Distribution and Reception of Holy Communion Under Both Kinds for the Dioceses of the United States of America, NDRHC, no. 28). When recourse is had to Extraordinary Minister of Holy Communion, especially in the distribution of Holy Communion under both kinds, their number should not be increased beyond what is required for the orderly and reverent distribution of the Body and Blood of the Lord. In all matters such Extraordinary Ministers of Holy Communion should follow the guidance of the diocesan bishop (IBID).
Usher
Ushers are ministers of hospitality, as are the greeteers. In addition to the greeters, the ushers assist in seating people when the number in attendance is great, aid the infirm or aged who require assitance, dispense materials on special occasions (e.g., sign-ups, hand-outs, etc.) distirbute bulletins, clean and prepare the church for the next service, aid those who become ill during a service, etc. It is an essential and much-needed ministry.
Sacristan
A sacristan is one who takes special care of the priests' and servers' sacristies. It is the ministry of this person to prepare the Church prior to Mass and to assist following the Mass.