Studies into the relationship between irrational beliefs and severity of depression have yielded variable results. Furthermore, there is a lack of information on the nature of this relationship within clinically depressed patients. The paper explores the relationship between BDI scores and individual irrational beliefs as measured by the Irrational Beliefs Test (IBT) in a clinical outpatient group (N = 63) with major and minor depressive disorders diagnosed according to Research Diagnostic Criteria, and in a comparison group of university students (N = 43). The results of MANOVA analyses showed that the two groups differed significantly in overall level of irrational beliefs and their endorsement of 7 out of 10 irrational belief scales. They also differed as to which irrational belief scale scores were predictive of BDI score. Findings suggested that several Rational Emotive Therapy constructs lack explanatory and predictive power with respect to depressive relationships.