Generally speaking, three distinct phenomena tend to hang together in human perception: perceiving that p, knowing that p, and knowing that one is perceiving that p. This chapter considers how these phenomena are related. I argue that understanding them in the context of a ‘Two-Tier’ epistemological framework, which I have developed in earlier work, automatically delivers an account of these relationships. In short, both perceptual knowledge (that p) and perceptual self-knowledge (that I am perceiving that p) are—in different ways, and for different reasons—explanatorily (but not epistemically) grounded in perceiving that p. The explanation turns in part on understanding perceptual self-knowledge as an aspect of our capacity for rational expression of our states of epistemic perception. We can get a feel for the nature of this capacity, I suggest, by focussing on its exercise in basic invitations to joint perceptual attention.