This book offers the first comprehensive discussion of Lacan's Kant with Sade, an essay widely recognised as one of his most important and difficult texts. Here, the reader will find a detailed roadmap for each section of the essay, including clarifications of the allusions, implicit borrowings and references in Lacan's text, unique insights into the essay's publication history, and a critical assessment of its reception. The author expertly defines key terms, explains complex theoretical arguments, and contextualises the work within a larger philosophical discourse. No prior knowledge of Lacan, Kant or Sade is assumed, allowing both newcomers and those who are well-versed in psychoanalysis, philosophy, and literary criticism to benefit from the book. This engaging book clears the path for a long overdue re-discovery and a proper appreciation of one of Lacan's most challenging works, inspiring a renewed debate on the significance of Lacanian psychoanalysis for moral philosophy and literary theory.