President Mary McAleese met Queen Elizabeth II in Hillsborough in Co Down today.
The President described as a 'cordial, friendly chat' with the monarch.
It was the first such meeting between a President and a British monarch to take place in Ireland.
Queen Elizabeth and her husband, the Duke of Edinburgh, arrived in Northern Ireland last night and undertook a series of engagements today.
Since she was elected President in 1997, Mrs McAleese has met the Queen on three occasions, twice in London and in 1998 at a ceremony in Belgium to officially open the Messines Peace Park.