It will see projects in Limerick, Wexford, Donegal, Westmeath and Waterford
Some 700 new jobs are to be created with new courthouses to be built around the country.
The Courts Service says four new courthouses are to be built and three others to undergo full refurbishments.
Planning arrangements have already been finalised, and access to the sites for construction teams will be granted from today.
Work is due to commence after Christmas.
The plan, costing €135m, will see seven projects in Cork, Letterkenny, Wexford, Limerick, Mullingar, Drogheda and Waterford.
It is to be delivered by way of a Public Private Partnership with BAM PPP PGGM Infrastructure Cooperatie U.A. (BAM).
The consortium will construct and deliver the projects and provide facilities management of the venues.
The Chief Justice Susan Denham, has welcomed the projects
She said the projects will create "a future which promises a great change in the axis of activity in the legal world of several cities and town's".
"The investment in these seven projects is the largest single investment in regional court structures in the history of the state".
"These projects will bring world class court facilities to each city or town. Each new courthouse will be of a standard befitting the serious nature of the business conducted there, and respectful of the dignity of the people who are called upon to appear in court, in any capacity", she added.
Work on the construction will take up to 24 months to complete, with plans to begin moving court business into the venues in 2017.
The projects include the design, build, finance and maintenance of facilities at seven courthouses: