Mr Dan Flinter has decided to step down as chief executive of Enterprise Ireland, vacating one of the most high-profile public sector jobs in the State.
Mr Flinter, who held the post for five years, said he was leaving Enterprise Ireland to pursue "new challenges" where his experience, "particularly in relation to the private sector", would be valuable.
Enterprise Ireland chairman Mr Pat Molloy said the board would immediately start seeking a replacement for Mr Flinter, who will remain until a new chief executive has been selected.
On behalf of the Enterprise Ireland board, Mr Molloy thanked Mr Flinter for his "personal drive, enthusiasm, commitment and effectiveness" in establishing and developing the agency.
The chief executive position, which will be publicly advertised, is likely to attract a large amount of interest, both from within and outside the public sector.
Likely applicants from within Enterprise Ireland could include Mr Flinter's fellow executive directors: Mr Peter Coyle, Mr Brendan Finucane, Mr Feargal O'Morain, Mr Mike Feeney, Mr Gerry Murphy and Mr Pat Maher.
Forfás chief executive Mr Martin Cronin, who previously worked for the IDA, is also likely to feature highly on a list of candidates.
Aged 53, Mr Flinter is a native of Athy, Co Kildare.
Until now, his career has been based entirely within the semi-state sector.
He joined the IDA in the early 1970s, subsequently becoming chief executive of Enterprise Ireland predecessor, Forbairt.
Mr Flinter also sits on the boards of Forfás and Digital Media District Limited, but his future in those roles was unclear yesterday.
In a statement, he thanked the Tánaiste, Ms Harney, and other ministers for their support throughout his tenure at Enterprise Ireland.
The Tánaiste, meanwhile, expressed her "deep appreciation for the enormous contribution" made by Mr Flinter and said he would be missed.
Ms Harney described him as "an innovative and enthusiastic driver in the development and promotion of Irish companies in the world marketplace".
Mr Flinter also expressed gratitude to all the Irish companies he had advised on export growth strategies and wished them well. He was unavailable for additional comment.
Enterprise Ireland's functions focus on the support of Irish firms that wish to grow and reach new markets.
The agency, which falls under the aegis of the Department of Enterprise, Trade and Employment, administers an annual budget of about €300 million. The body has offices across the Republic and in 30 international locations.
Mr Flinter's decision to leave Enterprise Ireland comes two months after a confidential report revealed high levels of dissatisfaction among the agency's client companies.
The Tánaiste said at that time that she was unconcerned about the report's findings.
The body's work has become particularly challenging over the past year, as Irish companies face up to growing competitiveness challenges.
Enterprise Ireland unveiled a shift in its investment strategy last month, marking a move away from employment grants for start-ups and small and medium enterprises in favour of investment for shares.
