The old mode of government was the patriarchate (see patriarch), but now for the most part the churches, all of which are self-governing, are each governed by a holy synod, a board of bishops and laymen, often appointed by the government; where the head of the church is called patriarch, he is often only the moderator of the synod. The number of Orthodox churches recognizing one another as such is indefinite because of the fluid state of the relations of Orthodox bishops in countries to which communicants have emigrated.
There are many churches apart from those directly under the patriarchs. A unique, ancient church is that of Mt. Sinai, made up of the monastery of St. Catherine and its subject houses. The archbishop is also abbot. The monastic community of Mt. Athos in Greece is of special interest.