By the statutes of the USG:
Art. 3: All Superiors General of Religious Institutes or Societies of Apostolic Life of pontifical right are members by right of this Union. Among these Superiors General are also to be considered Abbots Primate and Presidents of Monastic Congregations.
Art. 4: The Superiors General of Institutes of diocesan right may also join the Union as associate members, provided they inform the Council of the Union of their adhesion in writing.
Congregations that are not yet members of the USG and want to apply for membership, must write to the President of the USG explaining their reasons and also indicating:
- Founder, place and date of foundation
- A brief history
- Indicate pontifical or diocesan right
- Category of membership
- Purpose, mission
- Places of presence
- Number of members
- Members of the government team
- Residence of the General Government
- Email and phone numbers of the General and Secretary General
- Procurator's office: name and residence of the procurator