There is an "urgent need" for almost 2,000 nurses to meet the targets for mental health service delivery planned by the Vision for Change programme 10 years ago, according to the Psychiatric Nurses Association (PNA).
New figures from the HSE have revealed an "unacceptable slow pace of recruitment" of staff for mental health services.
In reply to parliamentary questions from Fianna Fáil Deputy James Browne, the HSE said there were 10,815 members of staff in mental health services in Ireland.
The Vision for Change programme set out, 10 years ago, a need for 12,778 members of staff to work in the area.
Peter Hughes, PNA general secretary, said the figures highlighted the "shamefully inadequate progress in the implementation" of what was intended to be a total reform of mental health services.
The HSE figures reveal that only 93 new staff were recruited this year despite soaring demand in all areas of mental health services.
"The hope promised in Vision for Change for a radically reformed mental health service is being lost," Mr Hughes said.
Derek Cunningham, a spokesperson for the PNA, said he was "surprised" at the figures, and was concerned, considering the "huge amount of demand for the services".
"The recruitment levels are just so slow and since we are 10 years on, it's just very disappointing," he told the Irish Independent.
In its pre-Budget 2018 submission, the National Youth Council of Ireland (NYCI) has urged the Government to spend €32m in youth mental health initiatives.
The mental health issue "still looms large in the lives of Irish young people", according to James Doorley, deputy director of the NYCI.
"While the overall number of people dying by suicide has declined, there has been an increase among young men."
Mr Doorley said it was of "particular concern" that the suicide rate for young people aged 15-19 in Ireland was the fourth highest in the EU.
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