The construct of metacognition appears in an ever increasing number and range of contexts in educational, developmental, and cognitive psychology. Can it retain its status as a useful construct in the face of such diverse application? Or is it merely an umbrella term for diverse mental phenomena that are loosely if at all connected? Here I argue for metacognition playing many diverse roles yet having key features that connect these in a shared framework. Proposed as central to this framework is the exercise of inhibitory cognitive control as a necessary condition for metacognitive competence. Also argued for is greater recognition of metacognition as a disposition, not just competence. As a disposition its foundations are epistemological, and its value and importance lie in supporting individuals' effective management of their own minds. This disposition puts them in maximum control of what they think and know and the processes they engage in to revise their beliefs, individually and in interaction with others.