The Anglican Communion (AC) is a Christian communion consisting of the autocephalous national and regional churches historically in full communion with the See of Canterbury. Member churches exercise jurisdictional independence but share a common heritage concerning Anglican identity and commitment to scripture, tradition, and reason as sources of authority. The Archbishop of Canterbury acts as a focus of unity, recognised as primus inter pares, but without formal authority in Anglican provinces outside of the Church of England. Most, but not all, member churches of the communion are the historic national or regional Anglican churches.