Almost 600 civil servants will take the summer off this year, mainly to be with their children during school holidays.
The "term-time" scheme is being run on an experimental basis - but in some offices it has been so popular the names of applicants have had to be picked out of a hat.
Under the scheme, staff can take off 10 to 13 weeks without pay during the summer holidays. However, they can arrange to have their remaining pay spread over the 52 weeks of the year.
The Department of Finance said yesterday that 658 civil servants applied for term-time leave. Some withdrew their applications and some were refused, but 569 have been granted the leave.
The scheme, negotiated between the Civil and Public Service Union and the Civil Service, has been run for three years on a pilot basis. It began at the Department of Social, Community and Family Affairs two years ago and was expanded to four departments last year. This year nine departments, employing a majority of the State's civil servants, are taking part.
It would be reviewed in September, when the CPSU would press for its extension to all Government departments, a union official, Ms Gaye Dalton, said. It is aimed at parents of children under 18 or people caring for an adult residing with them.
In the Revenue Commissioners' office in Limerick last year, the scheme was over-subscribed to the extent that the names of the successful applicants had to be picked out of a hat, she said.
The Civil Service will replace the people on the term-time scheme with temporary workers. Ms Dalton said 6,000 people applied for the temporary positions when they were advertised. This, she said, was at a time when "the Civil Service can't get people in to work permanently".
Temporary work suited many people's lifestyles more than permanent work, she said. Much of the temporary work arose in applicants' local areas, while a permanent job could mean moving to Dublin, where the cost of accommodation was prohibitively high. Temporary workers included women moving back into the workforce and third-level students, she said.
The union is also negotiating a "work-sharing" scheme in which civil servants could opt to work in a variety of ways, including a four-day week or mornings only.