Pfizer, the US pharmaceutical company, is to create 200 jobs with the establishment of a financial shared services centre in Dublin.
The multimillion investment will be supported by IDA Ireland, and is the first such project to be announced by the authority this year.
Welcoming the news, the Tánaiste, Ms Harney, said she was optimistic that additional "significant new investments" would be announced before the end of the first quarter.
"I base this on the high number of negotiations currently under way between IDA Ireland and some leading international companies," she said.
Pfizer's vice-president for finance operations in Europe, Mr George Henninger, who led the decision to locate the new operation in Dublin, said locations in more than 17 other countries had been considered.
Dublin's combination of infrastructure and people skills had made it the best choice, Mr Henninger said, highlighting telecommunications facilities and ease of international access as key benefits.
The Republic's low tax rate was not an important factor in the final decision, according to Mr Henninger.
The new operation, which will be located in the centre of Dublin, will be aimed at servicing the financial side of Pfizer's business across Europe.
The creation of the shared services centre will bring together functions currently carried out in a number of locations, such as purchase payments and general accounting.
Recruitment at the centre will be aimed towards candidates holding qualifications in finance, accounting, IT, with positions also open to people with multilingual skills.
Pfizer plans to fill about 130 jobs before the end of this year, with the remainder coming in 2004 and 2005.
The company, which is best known for the production of Viagra, already employs 1,600 people in manufacturing, sales and marketing in Cork and Dublin.
About 25 staff are also employed at Pfizer International Bank Europe in the International Financial Services Centre in Dublin.
"This new addition by Pfizer to its financial activities is an important decision for Ireland and will also serve to enhance IDA's position in its bid to attract further finance-type activities within the pharmaceutical sector," the Tánaiste said.
IDA chief executive Mr Seán Dorgan predicted last week that the first quarter of this year would be the best recorded since 2000 in investment terms.
Mr Dorgan highlighted the healthcare, pharmaceutical and internationally traded services sectors as those most likely to expand over coming months.
About 12,000 new jobs were created by IDA-backed companies last year, while almost 15,000 jobs had been lost over the same period.
The net result was a 2.2 per cent shrinkage in employment, with western regions being hardest hit.
