A coalition of the country's main Traveller organisations has accused the State of failing to provide 60% of the accommodation it was advised was needed over a decade ago.
The groups say local authorities have failed to draw down over €50m in government funding to improve Travellers' living conditions.
A spokesperson for Minister of State with responsibility for Housing Jan O'Sullivan said councils have given her reasons for under-spends.
She has now commissioned further research and inserted a mid-term review of new Traveller Accommodation to identify any under-spend.
Fingal Council said that in the past five years it has spent €18m maintaining and managing Traveller-specific accommodation.
It added that dealing with illegal dumping there is particularly challenging.