Minister for Transport Martin Cullen has launched a public consultation on the planned extension of the Luas to Citywest.
The 3.2 kilometre route, which it is hoped will carry over three million passengers per year, will branch off the existing Tallaght Red Line at Cookstown.
It will run through Cairnwood, Ambervale, Belgard, Fettercairn, Kilmartin, Cheeverstown, Brookfield, Ardmore and the Citywest Business Campus, terminating at Fortunestown Lane.
Park and Ride facilities have been planned for Cheeverstown, offering Luas options for motorists using the N7 Naas Road and N71 Blessington Road.
The project will be run on public private partnership basis involving the Railway Procurement Agency, South Dublin County Council and local developers. The public consultation runs until April.
Speaking today, Mr Cullen said the line would help sustain investment and jobs in the area.
"A new public transport service will be on offer to new communities with developers contributing to the cost. This means savings for taxpayers, not only in construction costs but significantly, in land costs too," he added.