Justice minister Helen McEntee has named Mark Toland as the inspector of prisons, on a temporary interim basis.
The vacancy arises following the resignation of Patricia Gilheaney as inspector with effect from 16 February.
A search by the Public Appointment Service was launched on 29 October to recruit a new inspector of prisons service and is expected to be completed shortly.
Toland took up his position as inspector of prisons on 18 February.
He is currently the chief inspector of the Garda Síochána Inspectorate and will continue in his current role during this interim appointment as inspector of prisons.