<p>Metacognition (the fundamental ability to reflect on and evaluate one’s own thoughts and actions) can shape human decisions and behaviours. Alterations in metacognition, such as distortions in confidence, self-reflection and beliefs about mental processes, are frequent in patients with mental disorders and are the target of effective clinical interventions. However, inconsistent frameworks and conceptual barriers between cognitive neuroscience and clinical disciplines have hindered advances in understanding and treating metacognition in psychopathology. In this Review, we review the metacognition literature to highlight cross-disciplinary inconsistencies and overlaps in terminology, experimental approaches and study populations between cognitive neuroscience and clinical perspectives. We build on a hierarchical framework of metacognition to start the process of integrating these literatures, and discuss the challenges associated with categorical and dimensional approaches to mental disorders. Our recommendations for future directions highlight the need for collaborative work between cognitive and clinical experts and methodological approaches that capture the causal links between metacognition and psychopathology.</p>