The Your Holiness reference article from the English Wikipedia on 24-Apr-2004
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Your Holiness

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Your Holiness is the formal style by which the Pope is addressed, and is properly the superlative style, taking precedence before all other styles. The Patriarch of Constantinople is also styled Your All Holiness.

Other ecclesiastical dignitaries enjoy inferior styles. A Cardinal of the Holy Roman Church enjoys the rank and precedence of a sovereign prince, and is styled Your Eminence. A Patriarch of an Eastern Rite Church is styled Your Beatitude, and an Archbishop or Bishop is styled Your Excellency.

The Dalai Lama is also addressed as with Your Holiness in English, though some have argued that this is a questionable translation of a word that could also be rendered Your Presence.