Teachers are launching legal action over Novopay to seek compensation for those left hurt, humiliated or out of pocket by ongoing payroll problems.
The Post Primary Teachers' Association (PPTA) president Angela Roberts said the national executive met at the weekend and resolved to allow its 18,000 members to take legal action.
Ms Roberts says with the government still "dithering" over helping those 1600 teachers affected, the association was left with little choice.
"Despite reassuring noises made by government representatives, as late in the piece as yesterday there were still no definite plans to roll out a resourced survival package for affected schools and their employees," she said.
"Members' patience and goodwill has all but run out. Continued Novopay errors mean schools, students, principals and administration staff are at the end of their tether."
The PPTA said discussions were under way with lawyers. Teachers who had suffered emotionally or financially were invited to join the suit.
The move comes days after cabinet minister Steven Joyce, who is responsible for Novopay, released details showing staff at 628 schools had been affected by problems with the payroll system.
It showed 521 teachers were overpaid, 589 were underpaid and 552 weren't paid at all.
Talent2, the company that supplies Novopay, released the first of three software upgrades last weekend, with others to follow in March and April.
A ministerial inquiry is investigating all aspects of the error-ridden system, which has caused strife since it was rolled out in August.