Up to 700 jobs are to be created during the development of seven courthouses around Ireland.
Four new courthouses are to be built in Drogheda, Letterkenny, Limerick and Wexford. Substantial refurbishment and extension works are planned for existing courthouses in Cork, Mullingar and Waterford.
Minister for Justice Frances Fitzgerald has welcomed the signing of the Public-Private Partnership (PPP) Project contracts.
"This PPP project represents a substantial investment in the modernisation of our court facilities with project costs estimated to be €135m which will provide an important boost to the local economies of seven regional cities and towns.
"It is expected that up to 700 new jobs are to be created during the period of construction," said Ms Fitzgerald.
The National Development Finance Agency signed the contract with BAM, the selected main contractor for Courts Bundle PPP Project.
The intention is that construction will start early in the New Year with a view to completing the work by December 2017.
Minister Fitzgerald said: "This Government has proved itself to be one of the most reforming in the history of the State when it comes to the courts and the legal system.
"It is only right that as we update our laws and legal systems that we also update our courts infrastructure."
The minister added that the project will be followed shortly by a further PPP project for the development of a new state-of-the-art family and children's court complex at Hammond Lane in Dublin.