This collection offers the first sustained, in-depth commentary on Seminar XX, Encore, considered the cornerstone of Lacan's work on the themes of sexual difference, knowledge, jouissance, and love. Although Seminar XX was originally popularized as Lacan's treatise on feminine sexuality, these essays, by some of today's foremost Lacanian scholars, go beyond feminine sexuality to address Lacan's significant intertwining concern with the rupture between reality and the real produced by modern science, and the implications of this rupture for subjectivity, knowledge, jouissance, and the body. The essays clarify basic concepts, but for readers already familiar with Lacan they also offer sophisticated workings-through of the more challenging and obscure arguments in Encore--both by tracing their historical development across Lacan's oeuvre and by demonstrating their relation to particular philosophical, theological, mathematical, and scientific concepts. They cover much of the terrain necessary for understanding sexual difference--not in terms of chromosomes, body parts, choice of sexual partner, or varieties of sexual practice--but in terms of one's position vis- -vis the Other and the kind of jouissance one is able to obtain. In so doing, they make significant interventions in the debates regarding sex, gender, and sexuality in feminist theory, philosophy, queer theory, and cultural studies.