75 There is yet another and quite different form of assistance given nowadays to missionary dioceses, which affords Us intense pleasure and which is deserving of notice before We bring this Encyclical Letter to an end. This is the active work undertaken by laymen under the direction of the Church in behalf of the new Christian communities. It consists for the most part in cooperating with the various national and international Catholic Institutes. The application of this assistance surely requires the zeal, the moderation, and the prudence that are proper in working for the good of others; but it is of great. benefit to dioceses harassed by insistent demands from fresh apostolic activities.
Source: Fidei Donum (Vatican.va)