Orthodox Christianity is an ancient, liturgical, sacramental, and eastern form of Christianity. Orthodox doctrine emphasizes the Trinity and Jesus Christís incarnation. Many Orthodox jurisdictions have immigrant roots from Greek, Arab, and Slavic nations, although Americans from other ethnic groups also convert to these churches. This family includes both Chalcedonian and non-Chaldecdonian Orthodox.
The following 23 Orthodox groups are included in the Religious Congregations & Membership Study 2010.