AbstractConcepts are our tools for thinking. They enable us to engage in explicit reasoning about things in the world. Like physical tools, they can be more or less good, given the ways we use them—more or less dependable for categorisation, learning, induction, action‐planning, and so on. Do concept users appreciate, explicitly or implicitly, that concepts vary in dependability? Do they feel that some concepts are in some way defective? If so, we metacognise our concepts. This article offers a preliminary taxonomy of different forms of metacognition directed at concepts and suggests that concept‐metacognition impacts on several different cognitive processes.