The Minister for Health James Reilly has said he has ruled nothing out in terms of a location for the new National Children's Hospital, including building on a greenfield site.
Last month, An Bord Pleanála refused planning permission to build the hospital on the Mater hospital site in Dublin, throwing into doubt the future of the project.
Terms of reference for the review group have now been agreed. The group will report back to Minister Reilly within 56 days of its first meeting.
After planning permission was refused, Minister Reilly set up the expert group under former HSE chairman Dr Frank Dolphin to examine the best location for the hospital.
The group will examine the project's planning considerations and look at the different options for the hospital - keeping in mind issues such as accessibility, paediatric services and best clinical practice.
Cost and value will be important, as will the quick turnaround of the project.
Speaking after the cabinet meeting, Minister Reilly said the group would look at all options, including the Mater site, other hospital locations and greenfield sites.