6,000 psychiatric nurses will begin industrial action this evening.
The Psychiatric Nurses' Association says its member will work only their contracted hours because of health management's failure to address a recruitment and retention crisis.
The PNA says the overtime ban will continue until the issue is resolved.
The HSE says it's putting measures in place to manage the situation.
Its spokesperson, David Walsh, is calling on the PNA to take part in talks at the Labour Court in an effort to resolve the dispute.
"The HSE recognises a significant problem in recruitment and retention of mental health nurses and we see the enhanced nurses' agreement agreed nationally earlier in the year as a major plank in addressing that," he said.
"We would ask the PNA to agree to a referral to the Labour Court to deal with the residual issues to do with that contract rather than engaging on the action that they now propose."
