IntroductionSchemas can be defined as the condensation of experience into an internal working model of the self, the other and the world. The schema concept has been successfully applied to a wide variety of psychiatric disorders (lit). To a much lesser extent the schema construct has been applied to psychotic disorders. Since paranoid ideation is by far the most common theme of delusions in psychotic disorders [1], it would be useful to gain a greater understanding of the contribution of schemas to the development of paranoid ideation. Over the last two decades, cognitive models have been developed that predict that negative cognitive schemas are involved in the formation and maintenance of persecutory delusions [2,3]. And it has been proposed that negative schemas about the self and negative schemas about others contribute independently to paranoid ideation [4,5]. Furthermore, some authors suggest that there is phase-specific activation of the negative self and other schemas in paranoid ideation [6,7]. Most importantly Bentall et al., 2008 predicted that the transition from risk states to clinical paranoia in the first episode of psychosis or recurrent psychotic episode is marked by a shift from negative beliefs about oneself to negative beliefs about others [6]. Therefore, to gain more information about schema activation in association with paranoid ideation, it would be useful to compare people at risk for psychosis with people with psychosis. One measure that covers negative schemas of self and others is the Brief Core Schema Scale (BCSS, [ 8]). Since its publication the BCSS has proven fruitful and has given rise to numerous publications based on non-clinical populations, for example [9-11] summarizing a large number of participants. In contrast, there are only a limited number of... half of the paper... clinical groups, especially among people with psychotic symptoms and people at risk compared to people with affective disorders and non-clinical controls. Hypotheses on the association of schemas and paranoid ideation. Negative evaluations of self and others are associated with suspiciousness and persecution in people in CHR [20,21] and in people with psychosis [8,15-17]. Although there is no clear pattern whether it is high negative self-expression or other schemas, respectively low positive self-expression or other schemas that predict paranoid ideation. The dynamic schema activation model proposed by Bentall et al. may explain these conflicting results. According to Bentall et al. we assume that paranoid ideation is predicted by negative beliefs about oneself in low-risk states and by negative beliefs about others in full-blown psychosis.