(Unsplash/Marc-Olivier Jodoin)
"Contacts with the laity, in the case of monastic or contemplative Institutes, take the form of a relationship that is primarily spiritual, while for Institutes involved in works of the apostolate these contacts also translate into forms of pastoral cooperation. Members of Secular Institutes, lay or clerical, relate to other members of the faithful at the level of everyday life. Today, often as a result of new situations, many Institutes have come to the conclusion that their charism can be shared with the laity. The laity are therefore invited to share more intensely in the spirituality and mission of these Institutes. We may say that, in the light of certain historical experiences such as those of the Secular or Third Orders, a new chapter, rich in hope, has begun in the history of relations between consecrated persons and the laity." (Vita Consecrata, Paragraph 54)
Associates, aka affiliates, are women and men, married or unmarried, who answer the Gospel call to holiness by formally associating themselves with a religious community. The mission, spirituality, or charism of the community is what draws an associate in, and also what animates the covenant or promise an associate takes in their mutual relationship with the community.
The associate movement is different from, say, secular institutes or third orders which are in canon law. Depending on who you talk to, some might say associations began shortly after the church began, when laypeople would bring supplies to desert monks or hermits. The laypeople associated themselves with these clerics or burgeoning religious communities, providing material needs or supplies, perhaps staying for a short time to receive blessings or instructions, imbuing their spirituality through the teachings and charisms they encountered and then bringing it back into their own lives in the world. Others, especially Dominican associates I know, suggest it wasn't until the Middle Ages that a more analogous associate movement began perhaps with St. Catherine of Siena.
However, I prefer to think that the current phenomenon of lay associates connected to congregations are a legacy of the Second Vatican Council, as most iterations of this movement can trace their beginnings to the late 1960s or 1970s. After all, Vatican II called for greater collaboration with the laity, and that is what associates are to me: the laity or non-vowed working together with the vowed or consecrated, bringing forth the Kingdom through our shared justice, ministerial, prayer and spiritual practices. It is the charism that the vowed members have begun to share, and what creates our mutual relationship. The church is a movement of movements, and associates are a dynamic part of the church today.
My wife, Regina, and I are part of the 3,400 Mercy associates within the Institute of the Sisters of Mercy of the Americas; since 2013 there have been more associates than sisters in this institute, and this is becoming more common. The 3,400 Mercy associates are but a fraction of the nearly 60,000 associates across the United States and Canada from over 300 men's and women's religious congregations.