This chapter highlights that the study of metacognition sheds light on some fundamental issues about consciousness and its role in behavior. It analyzes the long-standing issue of the cause-and-effect relation between consciousness and behavior. The chapter emphasizes the work on metacognition within the area of adult memory research. It examines questions on metacognitive judgments, emphasizing its implications for issues concerning consciousness; in particular, the genesis of subjective experience, the function of self-reflective consciousness, and the cause-and-effect relation between subjective experience and behavior. These questions explore the bases of metacognitive judgments, validity of subjective intuitions, the processes underlying the accuracy and inaccuracy of metacognitive judgments and strategic regulation of learning and remembering. In conclusion, the chapter comments on how the research on metacognition relates to some of the fundamental issues regarding consciousness and its role in behavior.