The Government has published legislation to reinstate elements of the Joint Labour Committee system of wage setting mechanisms.
The system, which provided legal guarantees of pay and conditions for around 200,000 workers, was found to be unconstitutional earlier this year.
However, the new system will see a reduction in pay and protections for many workers.
Under the new provisions, the number of Joint Labour Committees will be cut from 13 to six.
Previously there were around 300 different pay rates depending on experience and other factors but in future, JLCs can only set a basic adult rate and two increments for experience.
In future employers can either pay a premium for Sunday work, previously obligatory, or give the worker time off in lieu, which could hit take home pay.
Crucially, employers who can satisfy the Labour Court that they are in financial difficulty, will be able to derogate from the terms of a JLC for a period.
Among the factors that must be considered when establishing a JLC are comparable wage rates in similar sectors in other countries, although that must be done in a fair and reasonable manner.
The department insists that workers continue to be protected by their existing employment contracts, though some employment experts acknowledge that the new system gives fewer guarantees to workers.
'Five steps backward'
The Restaurants Association of Ireland has described the legislation published today as five steps backwards for the industry.
Chief Executive Adrian Cummins said they had wanted the system completely abolished.
SIPTU has said it is "disappointed" that the Sunday premium is not included in the legislation.
ISME said the new laws will do little to help small companies that are currently struggling.
ISME Chief Executive Mark Fielding said: "The reintroduction of these outdated arrangements will heap further pressure on businesses that are just about staying afloat."
Chair of Chambers Ireland HR Policy Council John Forde said: "On first review, the proposed legislation has many suggestions that are worth welcoming."