The country's mental handicap nurses are preparing for industrial action, unless hospital employers settle a pay claim.
The row centres on a decision to increase the wages of unqualified staff in the sector by up to 27%, a move which nurses claim effectively downgrades their position.
Staff have voted overwhelmingly in favour of industrial action.
If a meeting next week between the two sides fails to resolve the issue, Liam Doran of the INO says the nurse will take action.
"We will be aiming for the industrial action to hit the employers, cut back on paper work, a work-to-rule type of format and we always continue to maintain services of those most in need in the learning disability sector.
"It is a difficult area to have industrial action in but equally if we don't address this problem this area will lose its dedicated qualified professionals."