Joining Opus Dei is not like joining a typical organization You need to receive a vocation from God to become part of the faithful of Opus Dei. So how do you know if you have a vocation? Here the recommendations others have posted are relevant: get to know Opus Dei through its various activities open to everyone: Evenings of Recollection, Annual Retreats, spiritual direction with a priest or layman, etc. Opus Dei has centers in many cities (if you send me your city I can tell you if there is a center there). Though the priests of Opus Dei travel to other cities, it is easiest to get involved if there is a center in the city you’re in. If you decide that these activities are helpful to you, that you like the spirit of Opus Dei (making holy the work you do each day, growing closer to God through a deeper commitment to doing his will, etc.) then you can let a member know that you feel you have a vocation. It’s really between you and God. Opus Dei just helps you to be sure the vocation is there. But if you have received a vocation and Opus Dei agrees, membership is the next step. However, there are 1000 roads to heaven, and Opus Dei is only one. You don’t have to be a member to participate in the many activities that Opus Dei sponsors, all of which will be enormously helpful to your spiritual life. So get to an Evening of Recollection, go on a retreat, get involved in spiritual direction, and get to confession! Regardless of whether you have a vocation to Opus Dei, you will be growing closer to God and that’s the goal.