Metacognition is the capacity to reflect upon and evaluate cognition and behaviour. Long of interest to philosophers and psychologists, metacognition has recently become the target of research in the cognitive neurosciences. By combining brain imaging, computational modeling, neuropsychology and insights from psychiatry, the present book offers a picture of the metacognitive functions of the brain. Chapters cover the definition and measurement of metacognition in humans and non-human animals, the computational underpinnings of metacognitive judgments, the cognitive neuroscience of self-monitoring ranging from confidence to error-monitoring, and neuropsychiatric studies of disorders of metacognition. This book provides an invaluable overview of a rapidly emerging and important field within cognitive neuroscience.