The former president Mary McAleese has urged a Yes vote in the marriage referendum - saying it would stop gay citizens being treated as second-class.
Mrs McAleese says it has now been established that the referendum is neither adoption or surrogacy, but simply the right of gay couples to marry.
But campaigners on the No side say they disagree with Mrs McAleese, and that a Yes vote will limit the ability of the Oireachtas to give preference to opposite-sex couples in future.
The Referendum Commission has again intervened in the debate - with Justice Kevin Cross saying the constitution does not give opposite-sex couples an absolute right to access fertility services.
He says this means that access to such services - which is not part of the proposed amendment - would not automatically be granted to same-sex couples if the referendum is passed.
Our political correspondent Gavan Reilly reports.
