Evidence that repetitive negative thinking (RNT) is a shared feature of a number of disorders has prompted the need for transdiagnostic self-report instruments; that is, measures of RNT that can be administered to individuals irrespective of their diagnosis. The Repetitive Thinking Questionnaire (RTQ; McEvoy et al., 2010) was developed to meet this need, and its psychometric properties and capacity to predict psychopathology have been tested in undergraduate and clinically anxious samples.