Sister Outsider is a collection of essays focusing on race/racism, gender/sexism, sexual identity, and social class as these are enacted in a white-supremist, heterosexist, capitalist patriarchy (i.e. the United States). As a Black woman, lesbian, feminist, mother, poet, essayist, and political activist, Lorde's essays in this collection include her often quoted "The Master's Tools Will Never Dismantle the Master's House," an essay that radically challenges how white people "learn about" racism, or how men "learn about" women: "Women of today are still being called upon to stretch across the gap of male ignorance and to educate men as to our existence and our needs. This is an old and primary tool of all oppressors to keep the oppressed occupied with the master's concerns . . . ."

Her essay "Poetry is Not a Luxury" suggests that poetry is "illumination," and is a way to wed ideas and feeling, a way "we help give name to the nameless so it can be thought. The farthest horizons of our hopes and fears are cobbled by our poems, carved from the rock experiences of our daily lives." Other titles include "Sexism: An American Disease in Blackface," "Man Child: A Black Lesbian Feminist's Response" (on being the lesbian mother of a son), and "The Uses of Anger: Women Respond to Racism."