Secondary school teachers are to take industrial action from October 2nd.
It follows a ballot by the ASTI on foot of its rejection of the Haddington Road public service agreement.
65 per cent of the union's membership voted in favour of industrial action.
From Wednesday week, 17,000 secondary school teachers will withdraw from meetings that do not take place within normal school hours.
This will include school planning and policy development meetings, staff and parent teacher meetings, and in-service training for teachers.
ASTI members are also being directed to withdraw any co-operation with in-service organised for the new Junior Cycle Framework.
They've been instructed not to undertake any duties arising from vacated middle management posts, unless they are "pensionably remunerated".
ASTI General Secretary Pat King said while teachers are anxious not to disrupt their students' education, ASTI members had voted by a two to one majority in favour of industrial action.
