The aim of this chapter is to provide an outline of key concepts underpinning the nature of the physical self in terms of its content, structure and its relationship with self-esteem. The intention is to offer a framework that will stimulate and facilitate discussion about how physical literacy might interweave with self-perceptions. Importantly, it provides the theoretical background to the discussion of physical literacy and the development of a positive sense of self in Chapter 6. This chapter assimilates theoretical concepts with empirical research conducted over the past twenty years on physical self-perceptions, described in greater detail in Fox and Wilson (2008). It is written primarily from the perspectives of social psychologist, human developmentalist, teacher/educator and parent.