This chapter presents the central theoretical concepts of symbolic interactionist (SI) models as they relate to the themes of selfhood and identity. The aim is to provide an account of the self as first and foremost a social entity, a view that contradicts a number of the core assumptions underpinning psychologically inspired accounts of self-development. The chapter covers the theoretical ideas of Mead, Blumer and Cooley before turning to address the uses and elaboration of those ideas in the work of Goffman, Becker and Cohen. The applied section of the chapter uses SI ideas to consider a range of issues including the importance of the ‘social work self’ as a resource for assisting service-users; defining service-users’ problems; working with families; and combatting stigma.