Know the facts
The royals' taste for luxury travel – and the exorbitant costs that go with it – is well known. But many people assume the taxpayer only foots the bill for travel to and from official royal engagements.
Opinion polls consistently put support for a republic at around 20% - that's around 10 million adults. A minority, yes, but a substantial one – especially given the poor level of debate about the monarchy.
Why don't members of the royal family ever give press conferences or appear on news programmes? Why is it always press officers - rather than the Windsors themselves – that respond to negative royal stories?
It's because there is a longstanding convention that royals only ever give very carefully managed interviews, whose questions have been agreed in advance. The Queen doesn't give interviews at all.
Contrary to popular belief, the position of head of the commonwealth - currently held by the Queen - is not hereditary and will not automatically pass to Prince Charles. When the Queen dies the choice of the next head will be made collectively by commonwealth leaders.
In fact, a Yougov poll in 2009 found that fewer than one in four commonwealth citizens wanted Prince Charles to succeed the Queen as their head.
It's often assumed that because the Queen is head of the commonwealth, she is also head of state to all commonwealth countries.
In fact, the London Declaration of 1949 stated that republics could be member nations, recognising the British monarch as head of the commonwealth but not as head of state.