Metacognition - cognitive processes that apply to themselves - is becoming increasingly recognized as a fundamental aspect of human psychology. In this broad-ranging book, internationally renowned authors show how a full analysis of human reasoning and behaviour requires an understanding of both cognitive and metacognitive activities. Important insights from across social and cognitive psychology are drawn together to offer an unmatched overview of this major debate, and a number of key questions are addressed, including: Are metacognitive activities similar to standard cognitive processes, or do they represent a separate category? How do people reflect on their cognitive processes? Does our metacognitive knowledge affect our behavioural choices?