To date there has been no suitable scale for the self-assessment of irritability in the clinical situation. Existing scales have either included aspects of personality trait together with present state or they have been constructed on non-clinical populations. A self-assessment scale has been constructed which seeks to overcome such faults. Measures of depression and of anxiety are included, together with measures of outwardly directed irritability and inwardly directed irritability. This scale should be known as the Irritability, Depression, Anxiety--or IDA--Scale.