The groups provide services for people with disabilities, the elderly and other vulnerable people.
SIPTU members in Section 39 organisations have backed strike action in a row over pay.
The groups provide services for people with disabilities, the elderly and other vulnerable people.
A strike was backed by 96 per cent of members who voted.
The union says the ball is now firmly in the government's court, when representatives attend the Workplace Relations Commission for talks on Monday.

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