Line A: Abbey Street to Tallaght

This line will runs for 14km from the city centre, through the north inner-city, crossing the river south at Heuston rail station, before serving St. James, Rialto, Drimnagh, Bluebell, Red Cow, Cookstown and Tallaght. There will be a depot at Red Cow.

The will be the first line for completion, scheduled towards the end of 2002. 7km of track is on-street, the balance being on dedicated alignments and on the central reservation of the main Naas road (N7). The original terminus was to be in Middle Abbey Street but, with the Line C plan now final, this has been replaced by a stop in Lower Abbey Street where the two lines join.

The idea of opening a section of this line earlier in 2002 has been shown to be unworkable. Preliminary on-site work for this line started in August 1999. Full-scale construction is scheduled from spring 2000. 20 low-floor trams will carry 2,800 people per hour in each direction, with 5 minute headways at peak times. Journey time: 38 minutes.

Line B: St. Stephen's Green to Sandyford

This line will largely follow the route of the closed Harcourt Street railway line from Sandyford to the city centre (89km) serving Balally, Dundrum, Milltown and Ranelagh. There will be a short section of street running along Harcourt Street and St. Stephen's Green West (1km) in the city centre. A depot will be located at the end of the line at Sandyford. 13 low-floor trams will carry 3,000 people an hour in each direction with 5 minute intervals between vehicles at peak time (15 minutes otherwise).
Eventually trams on this line will dive underground through the city centre but the location of the tunnel portal has yet to be decided. The line will open in June 2003 but the section on reserved track between the Grand Canal and Sandyford could open in 2002. Journey time: 22 minutes. Recent proposals put to government suggest this line, being largely on an old rail bed, should be built as a Metro rather than Light Rail linking via the city centre tunnel to the proposed heavy rail line to Dublin Airport. (see below) Another possibility is opening it as light rail but constructing it for easy conversion to metro.

Line C: Abbey Street to Connolly Station

This short route is designed to link Line A (and the city centre) at Abbey Street Middle with Connolly mainline train station and Busaras, the provincial bus station. Future extension into the docklands development (including the proposed National Conference Centre) is planned. The route runs along Abbey Street Lower, Beresford Place, Store Street (Busaras), terminating at Harbourmaster Place at the back entrance of the newly remodelled Connolly Station. The public enquiry has rejected this proposed terminus due to the limited space available for such a busy stop. It will now have to be relocated - probably on the Connolly Station ramp. Although behind schedule compared to Line A, this short line could become operational more-or-less at the same time.
Line C extension: Connolly Station to docklands
Proposals for the National Conference Centre include provision for a tram stop in Mayor Street. This would lie on a proposed extension of Line C and would provide an interchange with a proposed rail station on a proposed underground system (see below). There is also concern that the proposed Luas alignment will have to be single track for some of its length, compromising service frequencies, and also that a new bridge it will cross must be high enough for the canal below to be navigable. The Line C extension could possibly terminate at the Point Theatre but its existence will depend on the opening of the National Conference Centre. The outcome of the planning enquiry into the conference centre is awaited.

Line D: Broadstone to Ballymun and Airport ('the Northside Line')

This line would form a northern extension to the underground section. Public consultation on possible routes is on-going. Two main options have been identified with several variants.

Option 1: Broadstone railway cutting (currently disused) to Liffey junction, alongside Maynooth line to Broombridge, Finglas, Ballygall, Glasnevin, Ballymun, M50 interchange, airport.
Option 2: Broadstone railway cutting to Liffey junction, Glasnevin, Ballymum, M50 interchange, airport. (Finglas to be served by future branch from Glasnevin).

Variants include longer underground sections to Glasnevin or Drumcondra and a route via Dublin City University.
It now seems likely that option 2 will be chosen as public consultation raised little response in Finglas

Underground: St. Stephen's Green to Broadstone

Exploratory drilling was completed at the end of 1999 to test the feasibility of this underground link connecting lines B and D through the city centre. The consultants have concluded that an underground tunnel is possible and suggested various candidate routes to the government.

Link Line
A street line from Smithfield (Line A) to Broadstone (Line D) is being considered. This would provide a connection for Line D with the rest of the system if it is complete before the underground section. In the long term, it would connect Lines A/C with Lines B/D which otherwise would be entirely separate.

Trams
Twenty Citadis 301A vehicles have been ordered from Alstom. Capacity: 235 people (60 seats).

Other Tentative Rail Plans
Recent reviews of rail services presented to government includes proposals for new rail developments: A further surface Light Rail Line from Harold's Cross to Drumcondra linking with Line D to Ballymum.
Orbital Light Rail Line from Tallaght to Clondalkin, Lucan, Blanchardstown and Dublin Airport.
Underground rail link through south central Dublin from the National Conference Centre or Connolly Station to Heuston Station via Pearce Station and St. Stephens Green. This could link with existing lines on the north side of Dublin to form a circle service. It could impact Luas as it parallels the Line A/C line between Connolly and Heuston Stations.
Airport Rail Line from existing Maynooth line at Broombridge. This would parallel Line D of Luas which also is to serve the airport. A suggestion is that Luas Line B be replaced by a heavy rail line linked to this airport line by tunnel.
Navan Rail Line via Blanchardstown and Dunboyne.
Electrification of lines to Kildare and Maynooth and integrating these with the underground.