The referendum to ease restrictions on divorce looks set to be passed according to a prediction by an exit poll by Red C commissioned by RTÉ and TG4.
The survey suggests a majority of 87% have voted in favour of the referendum with 12% voting against and 1% refusing to answer or saying they don't know.
The poll has a margin of error of 3% and was conducted in 156 locations around the country today.
The question put to voters focused on two issues about divorce.
The first regarded how long people must be living apart before applying for a divorce and the second related to the recognition of foreign divorces.
A Yes vote in the referendum would mean the Constitution would no longer require somebody to be living apart from a spouse for at least four years before applying for a divorce.
The Government has said that if there is a Yes vote, it would propose a law that spouses would have to have been living apart for at least two out of the previous three years before they can apply for a divorce.
A Yes vote would also make the recognition of foreign divorces explicit in the Constitution.
The Minister for Justice, Charlie Flanagan, has said that he intends to propose laws to make the rules regarding foreign divorces more consistent if there is a Yes vote.