The country's fire brigades are preparing for their busiest night of the year.
People are being urged to head to council-run events rather than illegal bonfires this Halloween.
Dublin Fire Brigade operators took more than 900 calls this day last year.
"We still had 65 bonfires which we attended last year. It is down on the year before and the year before that," said Dennis Keeley, Chief Fire Officer.
"What we are seeing though, is an increase in our ambulance and emergency responses to medical emergencies.
"So the message we want to get out this year is to ensure that children are well supervised [and] that people stand well back from bonfires.
"And really the big message is to encourage people to attend the organised events."
Meanwhile, motorists are being urged to be on the lookout for trick-or-treaters this evening.
AA Ireland called on motorists to be safety conscious, particularly when driving through estates and cul-de-sacs where a high number of children could be trick-or-treating.
They called on drivers to be aware of the darker conditions, calling for them to reduce their speed.
They said motorists should "be on the lookout for children who could step onto the street without looking, pedestrians who are accompanying their children while trick-or-treating, and animals who could be startled by fireworks."
AA Ireland offered the following tips to help people this Halloween:
Pet owners are also being encouraged to keep their animals locked indoors to keep them safe this evening.
The DSPCA said Halloween brings an influx in strays and injured animals.