The employers' group IBEC says a large majority of companies in Ireland believe a 'Yes' vote in the re-run of the Lisbon Treaty referendum is important for Irish exports.
The organisation says 86% of employers believe ratification of the treaty is important for firms that export to the EU.
Ninety-eight per cent also believe EU membership has been important to the success of Irish business.
IBEC claims there is currently a question mark over Ireland's relationship with the EU and a 'Yes' vote on October 2 would send a positive signal.