Personal Protection Officers are officers of the Metropolitan Police Royalty and Diplomatic Protection Department who are assigned for the personal protection of members of the Royal Family. It is not revealed which members of the family have 24-hour protection, but they are generally understood to include (at least) as of November 2011: The Queen and The Duke of Edinburgh; The Prince of Wales and The Duchess of Cornwall; The Duke and Duchess of Cambridge; Prince Harry; The Duke of York; Princess Beatrice; Princess Eugenie; The Earl and Countess of Wessex and The Princess Royal.
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Personal Protection Officer Wikipedia(Text) CC BY-SA