Major depression is characterised by ruminative thinking whilst worry is considered central in generalised anxiety disorder (GAD). However, not only do these two forms of repetitive negative thinking regularly co-occur in the same individual but similarities between worry and rumination are apparent. Adapting a methodology developed by Langlois et al. (Behav. Res. Therapy 38 (2000) 157-173), this study directly compared worry and rumination in a non-clinical population across a series of variables drawn from current models (appraisal, general descriptors and emotional reactions). Each of 149 female volunteers, with a wide range of age and backgrounds, identified a ruminative thought and a different worry and subsequently evaluated them using the Cognitive Intrusion Questionnaire. Significant within-subject differences were revealed on seven variables: chronicity, unpleasantness, reality of problem, future orientation, past orientation, feelings of worry and insecurity. There were no differences found between worry and rumination on appraisals and strategies, consistent with accounts that propose that worry and rumination share the same processes but involve different content (Cognitive Ther. Res. 24 (2000) 671-688).