This article examines how some of Simone de Beauvoir's ethical notions about the Self-Other relation explored in her theoretical philosophy of the 1940s were developed in her subsequent autobiography. It argues that Beauvoir represents reciprocal alterity in these autobiographical texts through a testimonial engagement with autobiography conceptualized as an act of bearing witness for the Other, through the privileging of various interlocutors and privileged others with whom "the real" is experienced and through a negotiation with the reader. The article also (...) explores the wider question of how Beauvoir's engagement with autobiography might constitute a mode of ethical engagement with the Other. (shrink)