The Chief Justice has warned the failure to address the problem of delays in Ireland's appeal court system could damage society and the economy.
Mrs Justice Susan Denham said serious delays of up to four and half years to hear Supreme Court appeals impact on the economy and Ireland's international reputation.
In a keynote speech to a seminar on the establishment of a new civil appeal court, the Chief Justice also said any changes to the courts system should not impinge on the independence of the judiciary.
The establishment of a new Court of Appeal was necessary to maintain the internationally recognised standing of Ireland as a democratic State "for the people, but also as a good place to do business," she said.
Mrs Justice Denham said current situation in the Supreme Court was "unsustainable, untenable and it cannot be defended".
Appeals certified now may not be heard until 2017. She said the speedy resolution of disputes was important in a successful economy.
The courts perform an important task in supervising the activities of regulatory bodies and it was important the supervisory jurisdiction of the courts be exercised promptly and efficiently, she said.
Delays in processing such legal challenges impede the efficient performance of regulatory bodies, she said.
While progress had been made in the establishment of a commercial court to fast track disputes, appeals from this court were still subject to the same delays before the Supreme Court.
While the number of High Courts had increased to 36, the Supreme Court had not expanded proportionately, creating a bottleneck for the hearing of appeals.
Last year there was a 21.2% increase in the number of appeals filed. The structure of the superior courts was not designed to cope with the volume and complexity of the litigation coming before it.
The judge said the independence of the judiciary was at the core of any democratic state and it was fundamental to democracy and the rule of law that the judiciary be independent.
She pointed to Ireland's international standing as regards the rule of law, which encompasses judicial independence and an effective courts system. A strong rule of law "propels prosperity" and was an important consideration for business people and investors when deciding to business in a country" she said.
The establishment of a new Court of Appeal placed between the High Court and the Supreme Court to hear civil and criminal appeals should now be provided for in the Constitution, she said.
Govt reaffirms intention to hold autumn referendum
The Government has reaffirmed its intention to hold a referendum in late autumn on the need for a court of appeal and a family court.
Minister for Justice Alan Shatter said it was quite clear that the Supreme Court was substantially overburdened by the cases coming before it.
He said that people were entitled to have their cases dealt with speedily.
Mr Shatter acknowledged that the time-frame was "ambitious" but said the Government was already involved in the consultative phase and believed it could bring forward a referendum within the relevant time scale.