The Rear-Admiral of the United Kingdom is a now honorary office generally held by a senior (possibly retired) Royal Navy admiral. Despite the title, the Rear-Admiral of the United Kingdom is usually a full admiral. He is the deputy to the Vice-Admiral of the United Kingdom, who is in turn deputy to the Lord High Admiral of the United Kingdom (an office that was vested from 1964–2011 to the Sovereign and is currently held by HRH The Duke of Edinburgh).
He is appointed by the Sovereign on the nomination of the First Sea Lord, and his name is published in the London Gazette by the Home Office. The Admiral usually retires at 70 years of age, but there have been admirals, such as Thomas Cochrane, 10th Earl of Dundonald, who have been over 80 before they retired from their office.