Taoiseach Enda Kenny last night led tributes to the former secretary of the Department of Finance TK Whitaker, who died last night just a month after turning 100.
Mr Whitaker is widely regarded as the most influential public servant in the history of the State.
Mr Kenny said Mr Whitaker changed life, lives and generations in Ireland.
"He had an innate understanding of our patrimony - what we inherit from our ancestors - our ingenuity, our elegance, our intellect, our artistry, industry and kindness, and how we could put this to work for our country and our people," he said.
Mr Kenny said in the last decades, he, more than any other person, was responsible for transforming our economy and public life.
"He had a rare vision for our country and its future. He was a gentleman and patriot.
In modern Irish history, Mr Kenny said Mr Whitaker was "both incomparable and irreplaceable".
Finance Minister Michael Noonan said Mr Whitaker's contribution to Irish society is widely known.
"The respect with which he is held by politicians of all hues speaks volumes for his legacy as a public servant," he said.
"He demonstrated his skill and positive influence in both managing the department itself, and strategically guiding national economic policies."
Fianna Fáil TD Seán Haughey praised Mr Whitaker as "an outstanding public servant who played a pivotal role" in the creation of modern Ireland.
Mr Whitaker spent 30 years in the Department of Finance - 13 in its most high-profile role.
His appointment to the most senior post within the department came during a period of economic stagnation.
Together with a small team of officials, Mr Whitaker prepared his ground-breaking report, 'Economic Development', in 1958.
This detailed document provided a framework that would influence economic policy in the country for decades to come.
By promoting free trade and encouraging inward investment, Mr Whitaker's influence helped to change the Irish economy away from previous introspective policies and turn it outwards to face the world.
His later achievements included being Central Bank governor, having senior roles in the ESRI and the National University of Ireland, his appointment to both Seanad Éireann and the Council of State, as well as his contribution to improving relations with Northern Ireland.