The IDA has welcomed the outcome of ballots at Bausch and Lomb, where a cost-saving plan will see 900 jobs saved.
The remaining workforce taking pay cuts and changes to their terms of employment. 200 people will lose their jobs.
In a statement this morning the IDA said the company has committed to invest in Waterford and it will support management and staff into the future.
Members of the TEEU last night joined their SIPTU colleagues in accepting the proposals.
"The workers believe it, and the workers have put their trust in the package … it's up to the company to fulfil their part of the package," said TEEU regional secretary Paddy Kavanagh.
"We'll be watching the company closely to make sure they invest fully in all the projects that they have committee themselves to, and we'll also be monitoring [to ensure] that there will be no further pay cuts."