We report a cross-sectional descriptive study of 90 new long-stay patients (NLS) (i.e. those who had been resident for six months to three years in Permai Mental Hospital, Johor) and studied from April to June, 1995. The age of this sample ranged from 18 to 85 years. Two subgroups were observed (i.e. younger NLS patients aged 18 to 34 years and older NLS patients aged 35 to 85 years). Among the younger NLS patients, the commonest diagnosis was schizophrenia (51.2%), followed by mental retardation with related problems (24.4%). Sixty-one percent of these younger patients had a history of serious violence or dangerous behaviour. Older NLS patients were likely to have a diagnosis of schizophrenia (79.6%), followed by mood disorder (6.1%) and dementia (4.1%). Forty seven percent of these older group had history of danger to others and 57.1% were at moderate or severe risk of non-deliberate self-harm. Focusing on the schizophrenic patients, all of them had some form of psychopathology, either positive, negative or general symptoms and about one-fourth were assessed to pose a risk for aggression.