An application for planning permission for the new National Children's Hospital is to be submitted to An Bord Pleanála this autumn.
Clearing of the St James's Hospital site is under way and once it has been fully cleared, construction will commence in 2015, subject to planning permission.
Eilish Hardiman, chief executive of the Children's Hospital Board, said today the plan is to transfer services to the new hospital in 2018.
Once a new design team has been appointed, there will be public consultation, including consultation with patients of the existing three children's hospital, families, staff and others.
In January, John Pollock was appointed as Programme Director for the National Paediatric Development Board, which is responsible for getting the facility built.
Last year, Ms Hardiman was appointed as CEO of the Children's Hospital Group, which is responsible for bringing all three children's hospitals together to work as one.
In January, a report for Minister for Health James Reilly recommended that Tallaght Hospital and Connolly Hospital Blanchardstown in Dublin be the locations for two new Urgent Care Centres to treat sick children, in addition to the new hospital.
Both hospitals lost out in a bid to be the location for the National Children's Hospital.
The Urgent Care Centres will be built and operational well in advance of the main hospital opening on the St James's Hospital campus.