A FEE-paying boys' school will break with tradition and admit girls for the first time in its 91-year history,
The €6,974-a-year Sandford Park School in Ranelagh, south Dublin, will become co-educational from September when girls will be accepted into all year groups.
The move comes at a challenging time for the fee-paying sector, which is suffering declining enrolments and cuts in state support.
The school said there were a number of reasons for the move, but the financial pressure being felt is likely to have been a major factor.
In recent years Sandford Park took the unusual step of using a bus advertising campaign in a bid to boost enrolments.
Widening the net to include girls opens up another potential revenue stream.
In the 2011/12 year, enrolments in Sandford were 216 compared with 256 in 2007/08.
A Department of Education inspectors report in January 2008 noted how the positive economic climate in the four previous years had contributed to a rise in enrolments at that time
Fee-paying schools are being doubly squeezed because of the changed economic circumstances.
While the 55 fee-paying schools nationwide enjoyed a surge in enrolments during the Celtic Tiger years, overall pupil numbers have been falling steadily since 2008.
The sector is under further pressure from the ongoing reduction in the number of teachers the State will pay for.
The two-point increase in the pupil-teacher ratio (PTR) in fee-paying schools from next September, up to 23:1, will translate into the loss of about 100 state-paid teachers.
That blow comes on top of the increase in the PTR for fee-paying schools introduced last September, and compares with 19:1 for schools in the free education scheme.
Education Minister Ruairi Quinn insists the schools have the resources, through fees charged, to employ teachers privately.
However, secondary school management body JMB said the loss of so many teachers will leave schools struggling to maintain the curriculum.
In another sign of the pressure on the fee-paying sector, a number of schools have contacted the Department of Education to ask about the possibility of joining the free education sector.
Sandford Park did not respond to an Irish Independent request for a comment on the move to co-educational.
A notice on its website says the decision was taken for a number of reasons, including a societal shift towards co-educational schools and a fulfilment of the original vision of its founder.
It adds that significant numbers of current and potential parents and feeder schools had expressed an interest in Sandford providing a co-educational environment.
It also says the move would allow the school to optimise the use of resources and infrastructure.
Glenstal Abbey boys' boarding school in Limerick has also announced plans to go co-educational, but has not fixed a date.