The aim of the present single-blind randomized-controlled therapy study is to assess the efficacy of a new form of Cognitive Behavioral Therapy for delusions with a focus on emotion regulation, improvement of self-esteem and sleep quality (CBTd-E) that will be applied in 25 individual sessions. Moreover, the study aims to test whether the efficacy of CBTd-E is mediated by the postulated processes. The main hypotheses are: