Pope Benedict did it. Queen Beatrix of the Netherlands did it. Ian Paisley did it. And now even Alex Ferguson is doing it: all stepped aside at a high point in their careers. Isn't it time for the Queen to consider following suit?
Support for the replacement of the British monarchy with an elected head of state has never been lower – just 22% in one poll last year.
But you don't have to be a supporter of hereditary monarchy, or the flummery and protocol of court life, to recognise that, in recent years, the Queen has played the hand that fate has dealt her with consummate skill. Many of that 22% of English republicans would agree with that.
The low point of her monarchy came when she withdrew from public life after the death of Princess Diana, giving the impression that she was stiff, or uncaring. Since then, she has reconnected with the public and her popularity has soared.
Nevertheless, the years are showing and a further slowing down is inevitable. She is sending Prince Charles to fill in for her at some engagements and she is generally avoiding long-haul flights. The Commonwealth summit in Sri Lanka is a case in point.
It is possible to continue like this, gradually fading away until some medical crisis intervenes, but it would be a downhill path.
It would be far better to quit while she still has some time to enjoy with her husband and family in the honoured role of mother, or grandmother, to the King.
An old quote, from 1947, when she was next in line to the throne, is sometimes dredged up to show her determination to die with her boots – or should that be her crown? – on.
It was made in a broadcast on her 21st birthday, when she stated: "I declare before you all that my whole life, whether it be long or short, shall be devoted to your service and the service of our great imperial family, to which we all belong."
The sense of duty is palpable, but it is cruel to hold an 87-year-old woman to a pledge made by an idealistic young woman in a different era.
The "great imperial family" she spoke of is gone, though it leaves an echo in the Commonwealth.
One of her greatest achievements was presiding over the, more or less, orderly post-war dissolution of the empire.
In Ireland, she was able to put the capstone on the peace process in her state visit to the Republic. In Northern Ireland, she suspended protocol to meet Martin McGuinness in a context where he was comfortable and shook hands with him.
This is an illustrious career and these are historic achievements, by any standards, but it won't get any better.
Abdication must, for her, carry memories of her uncle Edward VIII's forced abdication amid scandal and crisis.
Reclaiming the word by abdicating at a time of popularity could be her last opportunity to make history.
Her friends and the public should let her know that no one would think the worse of her if she set this final Royal precedent.