Iarnród Éireann has set up a new text alert system to allow passengers report bad behaviour on the DART.
Anyone who sees something that concerns them, or is the victim of an incident, can text TRAIN to 51444.
The text will alert the DART security centre and allow it to dispatch roving security teams - or where appropriate, alert Gardaí.
Spokesperson Jane Cregan said the centre will be staffed at all operational hours.
“If somebody does witness or is a victim of an incident of anti-social behaviour, it can be very distressing for them,” she said.
“So that is why have made the decision today; to put in this service that we hope will provide comfort to our customers if there is an incident of anti-social behaviour – but I would stress that these incidents are rare.”
The text should include the word TRAIN, followed by your location, carriage number where possible and any details.
Passengers will receive an automated response to confirm the message has been received.
Iarnród Éireann said the service will be extended out to other Dublin commuter routes in the coming weeks.
It is publicising the new service in DART carriages and stations from today.
In a statement, the rail company said the service is one of a number of new measures aimed at tackling bad behaviour.
The company is also increasing security patrols, installing new CCTV, increasing planning and cooperation with Gardaí and recruiting a senior security specialist.