Supernormality refers to the tendency to systematically deny the presence of common symptoms (e.g., intrusive thoughts). The current article describes the psychometric qualities of a 37-item self-report measure of supernormality (i.e., Supernormality Scale; SS). The SS was administered to nonclinical individuals (n=95), noncriminal psychiatric patients (n=28), nonpsychiatric delinquents (n=49), and a heterogeneous sample of forensic patients (n=59). Within the healthy control sample, some employees were instructed to feign supernormal behaviour, while others were asked to respond honestly to SS items. Findings indicate that the SS demonstrates adequate test-retest stability and internal consistency. In the forensic patient sample, elevated SS scores were significant related to denial of intrusive thoughts in a thought suppression paradigm. However, accuracy parameters for the SS (i.e., sensitivity and specificity) showed that there is room for improvement. Nevertheless, our findings indicate that the SS might be a useful research tool for measuring denial of common symptoms.