Healthcare workers, teachers, civil servants and bus and train drivers are among those taking part in strikes with members of 16 unions involved.
There was a strong turnout of workers around the local picket lines, despite the bitterly cold weather.
Here are some of the scenes as workers join the Province-wide show of strength.
1. Strike action
Craigavon Area Hospital midwives who joined the picket line on Thursday. PT03-242. Photo: Tony Hendron
2. Strike action
Dietitians from Craigavon Area Hospital pictured on picket duty. PT03-243. Photo: Tony Hendron
3. Strike action
Unison staff at Craigavon Area Hospital getting their message to politicians out on the picket line on Thursday morning. PT03-244. Photo: Tony Hendron
4. Strike action
Unison members on strike at Craigavon Area Hospital. PT03-245. Photo: Tony Hendron