The Moriarty Tribunal says its investigating links between former Taoiseach Charles Haughey and the sale of State lands at Glending in Co Wicklow.
The inquiry heard that 140 acres of woods containing valuable sand and gravel deposits was sold to Roadstone in 1990 without a public tendering process.
In an opening statement, Gerry Healy, SC, said Mr Haughey's financial advisor, the late Des Traynor, was a director and later chairman of Roadstone.
Mr Healy said the inquiry would be investigating who benefited from the Government decision and whether it was connected to the operation of Ansbacher accounts by Mr Traynor.
The hearings are expected to last two weeks.
