Three studies are presented as supportive validatory evidence for the Delusions-Symptoms-States Inventory (DSSI). Firstly, senior psychologists and psychiatrists were asked to allocate the 84 DSSI items to clinical syndromes. For 17 items the assignment did not correspond to that of the authors, e.g. ‘neurotic depression’ items alloted to ‘psychotic depression’. Secondly, further referees had to put these 17 items into the DSSI sets, e.g. state of anxiety. This was done as predicted in all but two cases. The third study used clinicians of varied experience to rate their patients according to the presence of the syndromes. These ratings broadly agreed with the patients' scores on the DSSI sets, and for nine of the twelve the association was statistically significant.