Rumination has been found to heighten angry mood and has been implicated in the maintenance of anger-control problems. Despite this, little is known about the nature of rumination in anger. In this study, 10 patients with anger-control problems were assessed using a semistructured interview to investigate whether they actively ruminated during and after an anger-instigating episode and whether they held positive or negative metacognitive beliefs about ruminating. All patients indicated that they ruminated both during and after an anger incident. Eight patients identified positive metacognitive beliefs concerning the benefits of rumination in improving understanding, preparation, and coping and promoting self-justification of one's behavior. All participants also identified negative metacognitive beliefs. These beliefs related to the adverse emotional impact of rumination and its detrimental effect on functioning and relationships. The conceptual and clinical implications of the study are discussed.