Basically it's just the name is different. The Episcopal Church has its roots in the Church of England, and is part of the Anglican Communion, meaning it is one of many churches around the world that consider themselves to be aligned as part of the Anglican Church. The Archbishop of Canterbury (The Rev Rowan Williams) is considered the spirituall head of the Anglican Communion. But the Anglican Communion does not have a central single authority, like a Pope, and so each of the member churches has its own leadership. In the US the Presiding Bishop of the Epsicopal Church is the Most Rev Dr. Katherine Jefferts Schori.
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