Almost 60% of people in emergency accommodation have been homeless for more than two years, according to a new report from The Dublin Simon Community.
The charity, which is releasing its annual report today, also said that it has seen a 70% increase in demand for its mental health support services - a "colossal increase", according to spokesman Sam McGuinness.
He said that some of the findings in the report are "extraordinary".
"Look at people in emergency accommodation," he said.
"90% of them are there more than six months, and we're looking at 60% of those are there more than two years.
"So that's extraordinary, and it's putting great pressure eon the services, and also the people who are in those services."