Scholarly feminist meditations on the inner diversity of the self are many and long-standing. While the inner diversity of the self takes many forms, significant numbers of feminists across disciplines have focused frequently on the empirical phenomenon of the self that is shaped through social life to have an inner configuration of multiple identities that are in tension—a contradictory array of identities that is discussed below has been sometimes referred to as borderlands identities. While feminist considerations have varied widely, they generally share common themes and significant analytic complexity. This complexity arises in part because the very idea of the inner diversity of the self that is socially derived inevitably invokes a wide array of related factors. These factors include issues of agency and autonomy, the imprint on humanity of social constructions of subordination, privilege, and social conflict, including gender hierarchies, the phenomenon of intersectionality, and concepts of the self and subjectivity. In this chapter, I offer a brief review of feminist engagement with the concept of borderlands identities as one form of inner diversity. This account attends to the origins of feminist concern with inner diversity, the social sources of borderland identity formations, and the lasting implications for feminist theory and feminist approaches to envisioning and realizing greater social justice for all.