Catechism of the Catholic Church
930 Alongside the different forms of consecrated life are "societies of apostolic life whose members without religious vows pursue the particular apostolic purpose of their society, and lead a life as brothers or sisters in common according to a particular manner of life, strive for the perfection of charity through the observance of the constitutions. Among these there are societies in which the members embrace the evangelical counsels" according to their constitutions. 475
English Translation of the Cathechism of the Catholic Church for the United States of America © 1997, United States Catholic Conference, Inc.