This book provides a historical analysis of one of Sigmund Freud’s least-studied cases, published in 1920 as The Psychogenesis of a Case of Homosexuality in a Woman. Scholars of sexuality often focus on Freud’s writings on male homosexuality, disregarding his views on homosexual women. This book serves as a corrective, renewing and reinvigorating interest in Freud, and demonstrating that his views on sexuality are as relevant today as ever. Part I introduces the case and explores Freud’s attitudes towards lesbianism, radical among his medical colleagues in the early twentieth century. It also puts Margarethe Csonka, the patient, at its centre. Michal Shapira considers Freud’s only treatment of a "female homosexual" and assesses Csonka’s background life before and after the encounter. Part II expands the case beyond the scientific-medical purview of the times and looks at the new opportunities afforded to women and assimilated Jews through growing equality and the modernization of urban life in 1920s Vienna. This book places Csonka’s case within the broader context of medical and psychological texts, Freud’s own writings, Jewish and queer history, and modern Vienna’s urban and art history. Sigmund Freud and his Patient Margarethe Csonka will be of great interest to psychoanalysts in practice and in training, and to readers interested in the history of gender and sexuality, feminism, modern European and urban history, the history of psychoanalysis, science and medicine, and the history of ideas.