The literature on metacognition in Alzheimer's disease points to there being implicit and explicit routes to the control and monitoring of memory. For instance, despite not being able to make predictions of performance which reflect future behavior, people with Alzheimer's disease can regulate effectively the amount of time they spend studying an item. Thus, empirical tasks from the metacognition literature shed some light on the idea of implicit awareness. But the complex pattern of preservation and impairment in metacognitive knowledge also points to other dimensions on which we need to consider patient awareness.