Throughout The Troubles, Northern Ireland's political parties took part in talks with the British and Irish governments.
In 1998, something called the Good Friday agreement was signed.
The idea was to get the Nationalists and Unionists working together in a Northern Ireland Assembly, that would make some decisions that were previously made by the UK government in London.
This is known as devolution.
A power-sharing group was set up, but there were problems.
There were allegations of spying and some of the political parties said they couldn't work with each other.
In 2002, the Northern Ireland Assembly was suspended and its decision-making duties were returned to the UK government.
But on 8 May, 2007, the Assembly was given back power.
And on 3 August 2007 the British Army officially ended its operations in Northern Ireland.