The General Introduction presents the Eucharist as the centre, source, and goal of Christian life, insisting that Christ is truly present in the Blessed Sacrament and is owed the adoration given to God. Reservation primarily serves viaticum and Communion of the sick, while adoration, exposition, processions, and congresses must remain rooted in the Mass and lead the faithful back to fuller sacramental participation. It sets norms for dignified reservation: a secure tabernacle, a visible lamp, suitable access for prayer, and sufficient renewal of the consecrated hosts. The rite of Communion outside Mass calls for reverent preparation, appropriate ministers and vestments, careful handling of the sacred species, an hour’s fast with concessions for the sick and elderly, and confession or perfect contrition when necessary. Communion during Mass remains the fullest participation, though frequent Communion outside Mass should be available to those unable to attend. The text regulates exposition, including the prohibition of celebrating Mass in the same place, the use of candles and incense, periods of silence, Scripture, music, and prayer, and the ministers permitted to give benediction. It also outlines diocesan oversight of Corpus Christi processions and Eucharistic congresses, whose programmes should combine Mass, catechesis, adoration, public witness, and charitable social action.