Dublin is to get new rail carriages to help reduce overcrowding.
The government has approved the ordering of 41 new carriages.
They will be in operation by 2021, and "increase capacity across the Greater Dublin Area rail network".
The carriages, which are costing €150m, will create 34% more space for passengers at peak times.
The Kildare Line, Maynooth Line and Northern Line are set to benefit the most, and during morning rush-hour.
The additional carriages will be used with the existing InterCity Railcar fleet resulting in longer train sets.
Anne Graham, CEO of the National Transport Authority, admitted capacity has become "a real issue, particularly on commuter services".
"While it will take two years before any of these carriages enter service, customers will be reassured by the very fact that they are on the way", she said.
Jim Meade, Chief Executive of Iarnród Éireann descrobed the new carriages as "a welcome boost in capacity for some of our busiest commuter routes".
The Transport Minister has called the investment "hugely significant" and said it will "deliver real benefits to rail commuters in the Greater Dublin Area".
Shane Ross said he wants "more and more people to make the switch to sustainable mobility".