The objective of this study was to offer some personal observations as to how melancholia can be diagnosed and differentiated from the non-melancholic depressive conditions.

Personal clinical and research-based observations are presented following a critique of common current strategies.

The paper offers views on the most differentiating clinical features, argues for adding illness course variables to symptoms and provides details of the Sydney Melancholic Prototypic Index, a measure with a high overall classification rate in differentiating melancholic and non-melancholic depression.

Greater precision in differentiating melancholic from non-melancholic depression is advanced by weighting signs and symptoms of psychomotor disturbance, as well as including illness correlates and family history in the diagnostic process.