The co-occurrence of Diogenes and Capgras syndromes, both unusual in themselves, would be expected to be rare. A MEDLINE search using the terms Diogenes, Capgras, self-neglect and domestic squalor revealed no previous reports of this combination of disorders. Both conditions are somewhat dubiously named as &#164 syndromes' when in fact they are probably no more than symptoms with different causes. Of particular interest in this case is the exacerbation of the self-neglect, characteristic of the Diogenes syndrome, by the delusional misidentification which marks the Capgras syndrome; as well as the reinforcement of the previously recognised association with frontal lobe pathology. The role of medication, though limited, is described. ( Int J Psych Clin Pract 2001; 5:75-76).