Around 9,000 local authority staff belonging to the Fórsa trade union are to ballot for industrial action up to and including strike action in a dispute over a job evaluation scheme for clerical and administrative staff.
The move could trigger pay rises for them over and above scheduled public service increases, increments or promotions.
Job evaluation allows the knowledge and skills associated with a particular post to be assessed, measured and "appropriately rewarded".
A similar evaluation in 2019 resulted in pay rises ranging from 6% to 13% for around 7,000 Health Service Executive support staff.
Speaking at the Fórsa Local Authorities online conference, National Secretary Peter Nolan said the ballot was a response to management's withdrawal from Labour Court proceedings on the long-running dispute.
He said that last year, the Labour Court had ordered Fórsa to present a business plan to support its claim.
The union had done this, he told delegates, but said the Local Government Management Association which represents employers in the sector had refused to return to the Labour Court.
Mr Nolan noted that almost 10,000 council jobs were lost following the financial crisis, and claimed services had only been maintained because staff had taken on additional responsibilities above their pay grades.
He also pointed to disparities in pay structures in local authorities, saying staff in grades including technicians, archivists, heritage officers, museum curators, environmental awareness officers, library staff, authorised officers and IT workers could be paid more or less depending on which of the 31 councils they work for.
"The pay system in local government lacks equality, consistency and fairness. Local authorities suffered the greatest reduction of numbers of employees during the austerity era, which has resulted in significant grade drift in the sector.
"Local authority workers deserve no less favourable treatment than colleagues in other sectors," he said.
Meanwhile, the trade union movement has ignored a whole section of the workforce associated with "Big Tech", financial services pharma and the gig economy, and needs to target recruitment in those areas, according to the leader Fórsa, Kervin Callinan.
Addressing Forsa's Local Government online conference, General Secretary Mr Callinan said it was time to "get serious" about boosting the strength of the movement - and pointed to sectors where trade unions had failed to make an impact.
"If we are honest we should admit that a whole section of the workforce that associated with 'Big Tech', ICT and Digital, FinTech and Accounting, and much of Financial Services, Pharma, Biomedical Services and the gig economy has been out of reach for and to an extent ignored by the trade union movement," he told delegates.
"I would like to lead an attempt to make us relevant to these workers and to make them part of our movement," he said.
Mr Callinan said the trade union movement's ability to speak with "maximum credibility" for workers - and to influence the future to best effect - would depend on whether they were successful.
He cited a recommendation in the ten-year-old Commission on Trade Unions that there should be a smaller number of sectoral unions, with pooled resources to the greatest degree possible.
"I want to initiate a fresh attempt to put these exhortations into practice. We know that avoiding them is not making us any stronger," he said.
Mr Callinan told delegates that Forsa has commissioned legal research to argue for better collective bargaining rights to the High Level Group currently considering the issue.
He said unions must be open to all possible solutions - statutory, constitutional and European - if they were to realise not just the right to organise, but to be heard and bargain collectively.
Mr Callinan also confirmed that he will be a candidate for the role of President of the Irish Congress of Trade Unions later this year.