The Health Service Executive has said agreement has been reached with health unions on the introduction of an extended working day and week in the HSE and HSE funded agencies.
The HSE said the overarching aim of the extended hours of service is to facilitate smoother patient flow and greater levels of discharge in all parts of the healthcare system over a seven-day week.
The agreement would see staff such as consultants, social workers and administrative staff rostered over seven days, as opposed to five.
Greater staffing levels in hospitals at weekends has long been seen as a way of combatting overcrowding and waiting lists.
"We want to thank the unions for their engagement," said HSE Chief Executive Bernard Gloster.
"This has been a priority of the Minister [for Health] Jennifer Carroll McNeill and the HSE, and we now look forward to implementing it, focussing on the two priorities of patient flow (ED) and the commencement of outpatient clinics outside routine hours," Mr Gloster said.
The HSE agreement was first reported by the Irish Independent.
The Fórsa trade union represents many of the health workers likely to be impacted by the extended hours service, including administrative staff.
In an update to members, the union said the agreement does not mean all services will be automatically changed.
"Where a service is considering changes in rostering arrangements and working hours, the HSE is required to engage in a process with staff and their trade union," Fórsa said.
For staff employed before 16 December 2008, and who have not been promoted after that date, there is no obligation to change existing working arrangements, unless they agree to do so on a voluntary basis.
Staff employed after 16 December 2008, or who have been promoted since this date, where the service is changing, may be requested to change their roster.
Where there is disagreement between staff and management over extended services, there is a disputes procedure which consists of a referral to a Joint Review Group.
If no agreement is reached through this group the next step is to refer the dispute to an independent adjudicator, who will issue a recommendation on the changes.
"Any proposal to extend services must be based on maintaining safe staffing," Fórsa said.
The Minister for Health has described the deal as "extraordinary agreement" which will mean more healthcare staff will be working across weekends.
Speaking on her way into Cabinet, Jennifer Carroll MacNeill said it is a huge change to work practices and it will mean "a good patient flow" while also getting more out of hospital infrastructure assets seven days a week.
"I am confident this is a much better, smarter way of working, a more predictable way for everyone and a much better patient experience."
The minister also said she is bringing a memo to Cabinet on new patient safety standards across hospitals to ensure their processes are tested and that they are complying with international standards.
She said the legislation has been worked on "for a long time" and reflected on its importance urgently as she referred to cases of maternal deaths, the hips surgeries and also sepsis cases in Emergency Departments.
