The HSE has announced that all acute inpatient psychiatric beds will close at St Bridget's Hospital in Ballinasloe, Co Galway by the end of the year.
The move follows a review of acute beds in the Galway/Roscommon area. It will lead to a reduction of 22 beds across the region from the end of 2013.
In a statement the HSE said resources needed to be "re-shaped and focused on community based care" to implement the Vision for Change plan.
It says community mental health teams will be developed and strengthened to provide care and treatment nearer to service users' homes. It's hoped this will reduce the need for acute hospital admissions.
35 acute inpatient beds will be maintained in Galway city and 22 acute inpatient beds will be in Roscommon. The HSE said there will be no impact for current inpatients in Ballinasloe because the bed reduction will take place on a phased basis.
An additional 15 new specialist beds will be provide in the acute mental health unit in Galway. These will include beds for eating disorders, psychiatry of later life and mental health intellectual disability.
The HSE says the changes will not result in job losses, as staff will be redeployed.