School secretaries and caretakers have attended a meeting at Fórsa headquarters in Dublin this evening ahead of planned strike action on Thursday.
The union has claimed the workers are being treated as "second-class citizens" as they are not being given access to public sector pensions and other entitlements.
Addressing members at this evening's meeting, Fórsa's Head of Education Andy Pike said it had a clear and strong mandate for strike action after 98% of those balloted voted to support the move.
"This has been going on for so many years, only the option of an indefinite strike stood a chance of getting the Government's attention, putting sufficient pressure on them and getting a deal over the line," Mr Pike said.
More than 2,600 school secretaries and caretakers, who are members of Fórsa, are due to begin indefinite strike action from Thursday.
School secretary Luisa Carty told this evening's meeting that they have never had an opportunity like this before to secure pension parity.
"We will see this through all the way," Ms Carty said.
School caretaker Dave Hearne told the meeting that there is a two-tier system in schools because they work alongside teachers and SNAs who get public service pensions.
"We need to stand up for ourselves, this is our last chance, and we have to take it," Mr Hearne said.
According to Fórsa, around 2,000 schools will be affected by the action.
The Department of Education has instructed schools to open as normal, but other unions have told their members to support the striking workers by refusing to carry out the duties of secretaries and caretakers.
Tomorrow, exploratory talks are due to be held at the Workplace Relations Commission (WRC) in a bid to resolve the dispute.
Union sources have said they are not confident ahead of tomorrow's meeting, describing it as "talks about talks" as opposed to an opportunity for meaningful negotiations.
As part of the action, a rally will be held at the Department of Public Expenditure on Thursday.
A spokesperson of the Department of Education and Youth said it recognises the vitally important role of secretaries and caretakers within school communities.
"In recent years, we have made progress in improving the terms and conditions of school secretaries," the department said.
"This has included secretaries being placed on the payroll of the department and linked to any increases in pay under public sector agreements, improved annual leave entitlements, improved maternity provisions and paid sick leave in excess of the statutory requirement," it added.
The department said that it will continue to engage with all parties in the coming period.
