Provida Mater Ecclesia (February 2, 1947) was an Apostolic Constitution by Pope Pius XII. The constitution address the origins and development of the Evangelical counsels.
Along with Primo Feliciter and Cum Sanctissimus the constitution Provida Mater Ecclesia provided the basis for Catholic secular institutes to receive their own legislation.
References
Provida Mater Ecclesia Wikipedia(Text) CC BY-SA