From Rhoda:

Being that it's the month of the Most Holy Rosary, there is no better time to consider joining the Rosary Confraternity, if you're not yet a member.  Most of us already pray the rosary more than the frequency obligated by the Confraternity.  The fruits of our prayers simply increase more than tenfold.  
 
The benefits of membership are:

1. The special protection of the Mother of God.
2. A share in the prayer of many hundreds of thousands of members the world over, even after death.
3. A share in the prayers, Masses and apostolic works of the entire Order of Preachers.
4. The intercession of the entire heavenly court.
5. Various plenary and partial indulgences.
6. Six times a year the Rosary Center publication THE ROSARY, LIGHT AND LIFE is sent to those members who wish it. Its purpose is to provide sound doctrine and spiritual guidance for readers everywhere.

Obligations:
 
Each member strives to pray the fifteen mysteries of the Rosary each week¹ (this does not bind under sin²), and must have his/her name inscribed in the register of the Confraternity. There are no meetings, and no dues. As we pray, we pray also for the intentions of all the other members of the Rosary Confraternity worldwide, living and deceased.
 
How to enroll:
https://rosarycenter.org/enroll-in-the-rosary-confraternity