X ensuring that the transfer of a mentally ill prisoner to a psychiatric facility is treated as a matter of the highest priority. Mentally ill prisoners treated in civil mental hospitals A mentally ill prisoner should be kept and cared for in a hospital facility which is adequately equipped and possesses appropriately trained staf. This could be a civil mental hospital or a specially equipped psychiatric facility within the prison system. From an ethical standpoint, it is appropriate for mentally ill prisoners to be hospitalised outside the prison system at institutions for which the public health service is responsible. On the other hand, it can be argued that the provision of psychiatric facilities within the prison system enables care to be administered in optimal security conditions, and the activities of medical and social services can be intensifed in that system. Whichever course is chosen, the accommodation capacity of the psychiatric facility in question should be adequate, because quite often there is a pro‑ longed waiting period before a necessary transfer is efected. The transfer of the person concerned to a psychiatric facility should be treated as a matter of highest priority. Prisoners who are regarded as dangerous as a result of a serious mental illness should not be placed in high‑security units instead of a psychiatric facility. These prisoners should have access, in a hospital environment, to treatment and appropriate therapeutic activities, administered by a sufcient number of qualifed staf to provide them with the required assistance.6 2.2 Psychiatric units in prison Specialised psychiatric units in prison as part of the prison health‑care service can serve various purposes. The most common function is the treatment of prisoners with mental health problems who are placed there either tem‑ porarily for treatment or while waiting for transfer to a community treatment facility. On rare occasions, psychiatric units inside the prison system can also be used for holding and treating persons who have been declared criminally irresponsible, mainly in the absence of a secure facility outside the prison 6. CPT/Inf (2008)33. Psychiatric care and treatment plans Page 31