Wikipedia
Communio is a federation of theological journals, founded in 1972 by Joseph Ratzinger, Hans Urs von Balthasar, Henri de Lubac, Walter Kasper, Marc Ouellet, Louis Bouyer and others. Communio, now published in fifteen editions (German, English, Spanish and many others), has become one of the most important journals of Catholic thought. The journals are independently edited, but also publish translations of each other's articles.
It is often considered to be the sister publication and theological rival to the journal Concilium, which was founded in 1965 intending to keep the " Spirit of Vatican II" in the Church after the sessions had ended and the Council fathers returned to their respective dioceses. That journal was founded by Johann Baptist Metz, Anton van den Boogaard, Paul Brand (theologian), Marie-Dominique Chenu, Yves Congar, Karl Rahner, Edward Schillebeeckx, and Hans Küng.[1]