Disability and other services in the voluntary sector will be disrupted as two days of rolling strike action in Galway, Mayo Cork, Kerry and Donegal begin today in a dispute over pay.
The action is being taken in an effort to improve terms and conditions of employment for health and social care professionals who have not received a pay rise since 2008.
Unions say up to a third of staff are leaving their jobs each year to seek better conditions elsewhere.
SIPTU official Adrian Kane says all unions involved in the campaign are considering escalating their action.
"This campaign is sponsored by not only SIPTU but with Forsa and the INMO as well.
"So we will be meeting the following week in congress to decide if we need to escalate this dispute.
"It's not something that we want to do but as I say, in the absence of any engagement from the government, we have no other option but to do this."