The Attorney General has confirmed that new inquests will be held for the 48 victims of the 1981 Stardust fire tragedy.
It follows a request last April from the families of the victims.
They have continued to campaign for answers as to the cause of the St Valentine's Day tragedy.
The Attorney General said he is satisfied that the holding of fresh inquests is, on balance, in the public interest and in the interests of justice.
In a statement issued by his office, Séamus Woulfe said that having carefully considered all aspects of the matter he has formed the opinion that fresh inquests into the Stardust deaths are advisable.
"This is because he considers that in the original inquests there was an insufficiency of inquiry as to how the deaths occurred, namely, a failure to sufficiently consider those of the surrounding circumstances that concern the cause or causes of the fire," the statement said.
On 14 February 1981, 48 people died and more than 200 were injured in the Stardust fire in Artane in Dublin.
Darragh Mackin, of Phoenix Law who acts for the Stardust Truth and Justice Committee, said: "The Attorney General has today confirmed that our clients' application for a fresh inquest has been successful.
"The families are delighted with today's decision, however would ask that their privacy is respected tonight."
On 2 April of this year, Phoenix Law, based in Belfast, made a formal application for a fresh investigation by way of an inquest.
The request was accompanied by 40,000 postcards signed by members of the public demanding that the truth be told about the disaster.
The development has been welcomed by Antoinette Keegan who lost two sisters, Mary and Martina, in the fire and who was badly injured in the crush.
She told RTÉ News that the subsequent tribunal failed to ask her about the fire.
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In 2009, following continuing pressure from the victims' families, the Government appointed Paul Coffey who is now a judge to review their case for a further investigation. He recommended that the tribunal finding of "probable arson" be removed from Mr Justice Ronan Keane's report.
In 2017, a further review of the relatives' claims was carried out by Mr Justice Pat McCartan.
Ms Keegan said that the almost four decade-long relatives' campaign uncovered evidence of "999" calls in tribunal transcripts that Dublin Fire Brigade was alerted simultaneously, at 1.43am on 14 February 1981, to a fire on a seat in the hall and to a fire in the roof space.
The Keane Tribunal concluded that the fire on the seat was the incident of "probable arson" that contributed to the deaths. It also found that one fire exit had remained locked throughout the blaze.
Ms Keegan says the fire on the seat was small at the time, that the burning ceiling of the converted jam factory came crashing down around her and her fellow dancers, killing 48 and injuring over 200 others.
Additional reporting Joe Little