International audienceEngaging in metacognition (evaluating, controlling, and representing cognitive states) is paramount for efficient behaviour. In this Review, we examine different types of cognitive architectures that might be at play when people provide metacognitive judgements in the domains of memory and perception. Building upon this conceptual framework, we review evidence supporting and challenging domain-general metacognition. We also discuss commonalities in metacognition across domains, focusing on the influence of decisional processes on metacognitive judgements. We emphasize the challenges of isolating metacognitive processes and how these challenges influence conclusions regarding the domain generality of metacognition, incl...