The National Transport Authority has been assigned as the designated Approving Authority for the BusConnects, DART Expansion and MetroLink projects.
BusConnects will impact Dublin Bus users in Celbridge, Leixlip, Maynooth and Ballymore Eustace.
The DART expansion will also service customers along the Maynooth line.
The NTA has been put in this role to strengthen the oversight of the projects.
It will work with Iarnród Éireann and Transport Infrastructure Ireland on the expansion of the Dart and MetroLink respectively.