A study published in the March 2009 issue of Schizophrenia Research examines the complex relationship between chronic insomnia and paranoid ideation. Previous research has found that insomnia is a potential cause of anxiety, depression, and hallucinations while separate research has shown that these same factors are predictors of paranoia. In the present study, the authors examined for the first time the association of insomnia symptoms and paranoia in the general population and the extent of insomnia in psychiatric patients with persecutory delusions. Using a sample of 00 individuals from the general population and 30 individuals with persecutory delusions and a diagnosis of non-affective psychosis, assessments of insomnia, persecutory ideation, anxiety, and depression were for both samples. The results indicated that Moderate or severe insomnia was present in more than 50% of the delusions group. Consistent with the theoretical understanding of paranoia, the association was partly explained by the presence of anxiety and depression. The study provides the first direct evidence that insomnia is common in individuals with high levels of paranoia. It is plausible that sleep difficulties contribute to the development of persecutory ideation and that successful insomnia treatment for this group could have the added benefit of lessening paranoia.