Nurses in Northern Ireland will go on strike over staffing numbers and pay disputes on 18 December, the Royal College of Nursing (RCN) has said.
The union said its members were planning 12 hours of strike action, having voted for the move last week.
There are more dates of strike action planned for the new year.
The first day of industrial action, which includes refusing to do any task that is not patient-specific, will be on 3 December.
The industrial action will also include not working overtime, not working unpaid hours and not completing paperwork other than individual paper records.
It is the first time in the RCN's 103-year-history such action has been taken in the UK.
In a ballot held over four weeks, nurses were asked if they were willing to take industrial action, including strike action.
The RCN's Northern Ireland director Pat Cullen said after the vote last week that nurses had spoken clearly .