John and Shel Goldstein hug during a group wedding in Florida on 6 January, the day the state lifted its ban on same-sex marriage. AP / Press Association Images AP / Press Association Images / Press Association Images

IRISH CITIZENS WILL soon get the chance to vote on whether or not the following sentence should be added to the Constitution:

‘Marriage may be contracted in accordance with law by two persons without distinction as to their sex.’

In anticipation of May’s vote, people from both the ‘Yes’ and ‘No’ sides have started to publicly debate the issue in earnest.

If the Referendum is passed, Ireland will become the 20th country where same-sex marriage is legal. Civil partnership was introduced here in 2011.

Thomas Cahalan and Nicholas Nelson became the second male couple in Ireland to enter into a civil partnership in 2011. Leon Farrell / Photocall Ireland Leon Farrell / Photocall Ireland / Photocall Ireland

Senator Katherine Zappone at a pro-marriage equality protest in 2012. Laura Hutton / Photocall Ireland Laura Hutton / Photocall Ireland / Photocall Ireland

Here’s a breakdown of where gay couples can marry and when the relevant legislation took effect:

Note: Same-sex marriage is also legal in certain states in the US and Mexico.

Here are some photos of happy couples on their wedding days: