The hospital, along with a community day centre for outpatients at Usher's Island, forms part of the National Forensic Mental Health Service.

The hospital originally opened as the Central Criminal Lunatic Asylum for Ireland at Dundrum in Dublin in 1850.

This was an early move of an initiative throughout the United Kingdom and its colonies which included the building of Broadmoor Hospital in England.

[1] The site was originally chosen to be soothing to mental health patients and was intentionally not linked to any particular prison service to maintain the distinction between criminality and illness.

[3] The construction works were undertaken by Rhatigan OHL at a cost of €140 million.