The Department of Finance has appointed a civil servant at the Department at Health to one of the most high-profile roles within its budgetary and economic division.
Mr Derek Moran, a former principal officer at the Department of Health, has replaced Mr Cathal O'Loghlin as head of the economic policy unit, a section that works closely with the Minister for Finance, Mr McCreevy.
Mr O'Loghlin has meanwhile moved to Washington, where he has been appointed as an alternate director of the International Monetary Fund (IMF).
He took up the executive position of alternate director in the Canadian/Irish constituency in May, and will be involved in conducting the day-to-day business of the fund.
Mr Moran was employed by the Department of Health for just a few months before his new appointment.
He worked on the Strategy Implementation Team, which focuses on the development of national health policy.
He was previously based in the Department of Finance, where he focused mainly on budgetary matters.
It is believed that more than 20 individuals applied for the new position, which involves directing and managing the provision of key policy advice to the Minister for Finance.
The job, which was advertised at the end of May, calls for a thorough knowledge of economic theory and principles.
Applications for the role are thought to have come from both the public and private sectors.