A collection of fifteen essays written between 1976 and 1984 gives clear voice to Audre Lorde's literary and philosophical personae. These essays explore and illuminate the roots of Lorde's intellectual development and her deep-seated and longstanding concerns about ways of increasing empowerment among minority women writers and the absolute necessity to explicate the concept of difference—difference according to sex, race, and economic status. The title Sister Outsider finds its source in her poetry collection The Black Unicorn (1978).

These poems and the essays in Sister Outsider stress Lorde's oft-stated theme of continuity, particularly of the geographical and intellectual link between Dahomey, Africa, and her emerging self.