Indeed, the relation between the two constructs is generally thought to be bidirectional in nature. Without memory for one's past personal experiences, one's sense of self-one's personal identitywould be impoverished. In Wilson and Ross's (2003) words, "we are what we remember" (p.137). But equally, without a sense of self one would be unable to appreciate the personal significance of the events that one experiences. That there is a link between the two is undeniable. However, the precise nature of the relation requires careful consideration, and is likely to be far more complex and subtle than one might imagine at first glance. This is, in no small part, because memory and the self are not unitary entities, but multifaceted in nature (despite what introspection tells us). Hence, the relation between memory and the self requires careful unpacking. In this chapter, we start by considering some definitions of memory and the self. We then consider in some detail how memory and the self might be related on the psychological level. We then consider the relevance of these theories to autism spectrum disorder, providing a critical review of relevant research on the self in autism, followed by some hypotheses concerning how diminished sense of self might predict and explain the unique memory profile we see in the ASD population. Facets of Memory The idea that memory consists of multiple systems is now widely accepted (e.g. Schacter & Tulving, 1994). For the current purposes, one of the most important distinctions to have been drawn is between episodic and semantic memory (e.g., Tulving, 2001). Broadly, these hypothetical, functionally distinct, but interactive neuro-cognitive systems are thought to underpin long-term memory for