Self-criticism is a form of negative self-evaluation that has strong associations with many forms of psychopathology. Rumination is a maladaptive form of repetitive thinking that is associated with many psychological disorders. Although measures of several different types of rumination (e.g., general rumination, depressive rumination, anger rumination) have been developed, none focuses specifically on self-critical rumination. An initial pool of items addressing self-critical rumination was developed by adapting items from existing rumination measures and through a writing task administered to both student and clinical samples. Following an evaluation of content validity, 24 items were administered to a large sample of undergraduates along with measures of related constructs. The final 10-item version of the Self-Critical Rumination Scale showed excellent internal consistency, a clear single-factor structure, convergent relationships with related constructs, and incremental validity over other measures of self-criticism and rumination in predicting both general distress and features of borderline personality disorder.