About 20,000 retail staff are returning to work this morning, as some restrictions ease.
Under phase one of the roadmap, hardware, electrical, IT and phone shops can all reopen.
Outdoor workers, like construction staff, will also return to employment.
But the HSE's chief clinical officer, Dr Colm Henry, is urging people to be cautious.
"What's clear from the modelling is if you reverse very quickly, if those restrictions either ease or people's compliance disappears, it goes back up very quickly.
"So the R value, which is now 0.5, would rapidly rise."
