The circle is given by a married member of Opus Dei (supernumerary). The circle starts and ends with prayer, after the first prayer a gospel commentary from the days reading is given, a talk on a topic to help with formation, an examination conscience, and finally announcements for any upcoming events, reminders of confession and Evenings of Recollection before the final prayer.
I go to my circle to help remind me why I am trying to live a Plan of Life, to focus and bring me back to my goal of Holiness! The topic is ALWAYS helpful to me and makes me think even in the hardest times of life. This again is a co-operators circle as I understand them.