Childcare staff, drug rehab workers and members of the travelling community marched to the Department of Finance today to fight proposed An Bord Snip Nua funding cuts.
Around 500 people from Community Development Projects (CDPs) running youth clubs, meals on wheels services and education projects gathered to protest against the potential axing of €44 million.
Organisers warned the cuts to more than 180 local schemes would devastate some of the country's most disadvantaged areas.
Among the marchers was Cathleen O'Neill from the Kilbarrack CDP in Dublin.
"We're funded €104,000 a year — what difference will that make to those men in there?" she said.
"Today is about us standing together, mobilising our communities and sharing our skills to fight the cutbacks, otherwise you'll see decimated, destabilised communities."
The potential blow comes just months after a 15 per cent funding cut from the Department of Community, Rural and Gaeltacht Affairs.
Siptu organiser Darragh O'Connor said the latest proposed cutbacks — which would also hit Local Partnerships — would undoubtedly lead to project closures.
"The communities that have benefited least from the Celtic Tiger years are going to doubly suffer through tax rises and through the essential services in those communities which are also going to disappear," he said.
Mr O'Connor described the McCarthy report as an all-out attack on the community sector.
"If we don't do anything about it there will not be a community sector in six months' time or a year's time," he added.
CDPs employ a core staff of 300 people, with a further 1,400 workers involved indirectly.
Martin Collins from the Pavee Point Travellers' Centre in Dublin said the fight against cutbacks and resulting job losses would continue.
"There is a great sense of solidarity and a great sense of support, so you haven't seen anything yet," he said.
"We provide a very valuable service to these communities and this will be an ongoing, sustained campaign."